Number 9 must be the obligatory Melksham answer  as it looks like it is from the 'A to Z' list of departures for Melksham. The journey times would suggest the destination is Salisbury. The 19:17 weekday departure being shown as a connection instead of a through service leads me to believe that this is for the upcoming timetable change so the year is 2021.

The schedules are for light locomotives running as route learner/refresher trips for Freightliner drivers ready for upcoming engineering work on the Yeovil to Dorchester line. Even though the data has been 'scrambled' for RTT^» (Real Time Trains - website), the four digit train identity beginning with a zero denotes a light locomotive. The eight digit TSC code is for Freightliner.

I thought that calling it 'The Melksham Line' in the same vein as 'The Varsity Line' or 'The Heart of Wessex Line' sounded a bit nicer than plain old Thingley Junction to Bradford Junction! Perhaps 'The Lacock Line' or 'The Broughton Gifford Line' might have made it sound even more quaint!    As you say, it is an overlooked route until something goes awry on the 'Berks & Hants' route and then it is correctly seen as the crucial section of infrastructure that it is, so much so that it gets flogged beyond its capacity with local services often sacrificed to allow the diverted traffic through. Melksham Loop Now! 

The team that inadvertently severed the cable had to halt their repair efforts and return that evening after adequate rest as they had reached their limit for hours worked. Affected points were clipped and trains talked past signals, albeit with significant delay and disruption. Unfortunately, alternative methods of degraded working such as Temporary Block Working and Emergency Special Working weren't possible owing to the Absolute Block section between Lostwithiel and Par.

It was between Lostwithiel and Par. During cable renewal work, one was unfortunately severed. Not sure that it would have been sorted any faster east of Exeter as the Melksham line was disrupted for days when a signalling cable was severed a few months ago.

The 17:50 Gloucester to Southampton Central service (via Swindon) service will be starting at Westbury as the unit for the service at Gloucester has a fault.

I understand that because of the forecasted severe weather tonight, Network Rail have requested that the first scheduled services on specific 'at risk' routes must run as empty coaching stock to confirm that the tracks are free from obstructions such as debris and flood water. This would explain why the return working is not showing as cancelled.

Staffords Bridge, located between Cowley Bridge Junction and Stoke Canon, is the problem (again). The line there is closed once the water has risen to a predetermined level. The water level there hasn't yet receded below the mark at which the line can be reopened. Once it has, a bridge examiner must confirm the integrity of the structure before trains can cross it. This is not expected to be possible until tomorrow morning.

The 75% number was based on the Sir Peter Hendy response yesterday for predicted availability at the depot next week, although I am not sure whether that was just the drivers or all grades. He would appear to be way off then? If so that'll teach me to check his figures before posting. However, that is inclusive of those self-isolating as a precautionary measure. It is probable (although not definite) that a large percentage of the precautionary self-isolating staff will not have caught the virus and therefore would most certainly not see Public Health England launch an investigation. However, if a large proportion of those do subsequently test positive, then you may well be right.

It is 75% of one depot, not 75% of the entire organisation. With the best will in the world, it is impossible to fully mitigate against such a local event happening as staff do have lives outside of work that will see them interact with others such as partners and children. The important thing to do is to take sufficient action to prevent it spreading to other locations. Those that follow rugby union may be aware that the professional clubs are following strict protocols such as social distancing, regular testing and player 'bubbles'. This hasn't prevented an outbreak at Exeter Chiefs (in my opinion an extremely professional and well run club) and has seen them have to forfeit their next match owing to the squad self-isolating. Their opponents from last week, Glasgow Warriors, have had to do likewise after being in contact with them. It shows it is not as easy as saying there are measures in place so it won't happen.

Back to railways, I know that Bristol had a lot of staff unavailable for similar reasons earlier this year, however the effects were less noticeable because of the reduced timetable in operation at the time. Large 'urban' depots such as Paddington, Bristol and Plymouth will be more susceptible than smaller 'rural' depots such as Par and Westbury because of the surrounding environs where the staff live and interact with the outside world. It is also unsurprising that these outbreaks have coincided with the colder weather and reduced daylight where staff are more likely to be inside for longer periods than outside. In the summer, there were plenty of staff who would take their break outside in the fresh air. Understandably, this is less appealing at this time of year.

I am of the opinion that reinstating more trains at the recent timetable change wasn't the best move at this time of year and has exacerbated the problem as I am sure that there will be further localised outbreaks at depots this winter.

Well spotted. Should say stage 6 (Hay Lane to Thingley and Hullavington) March 1968 instead. I had a pile of notices in front of me and read the date from the wrong one. D'oh!

Stage two was the abolition of Chippenham East SB^▸ (Signal Box) and the closure of Langley Crossing box.

Chippenham station has seen numerous alterations over the course of its history. The original station, opened in 1841 and built in an Italianate style, was heavily altered after the completion of the route to Weymouth and Salisbury in the 1850s. An island platform was built, creating a down direction bay and a train shed was provided. A bay for Calne services was provided at the up end of the island platform. The train shed was removed in the early 1900s and replaced with the canopies that are still there today. At the turn of the century, the down bay platform was converted to a through line, however being controlled by both West and East signal boxes required special working arrangements. To negate this, the bay was soon re-established by the erection of back-to-back buffer stops, with the line to the east of the buffers becoming a siding with the curious name of 'New Found Out' (NFO).

The excellent post by Bradshaw shows the dates for the closure of the various sections of infrastructure at Chippenham.

Chippenham was resignalled with Multiple Aspect Signalling, coming under the control of Swindon PSB^▸ (Power Signal Box) as part of Stage 2 (Wootton Bassett to Thingley) of the Swindon resignalling scheme in December 1966.

The slewing of the track to the island platform required the demolition of a wooden station building. A refreshment room stood behind the buffer stops of the Calne bay, adjacent to what would have been the NFO siding. This was demolished in 1975. This allowed the former Calne bay to be completely infilled, as it had already been partially infilled with a ramp down to a barrow crossing leading to the east end of the original down main platform following the Calne branch closure. This allowed the down main line to be slewed across to the island platform, allowing a complete HST^▸ (High Speed Train) formation to be accommodated at the platform. What is now the down main line is,  to the west of the original footbridge, the location of the down bay. East of the footbridge is the location of the NFO siding.

For anyone who may be interested, the location of the demolished wooden building is easily identifiable today. The canopy at the eastern end of the current down platform stops abruptly and retreats away at a right angle away from the edge of the down platform. This was where the building was situated. The filled in Calne bay is also identifiable for the same reason with the canopy only covering half of the island platform at the eastern end of the station. The former Fish Dock and the former Parcels Dock are also still extant at the east end of the station near the current taxi rank.

Avonmouth.

It appears that a road vehicle has struck one of the bridge parapets (road over rail) and knocked some of the masonry onto the track before leaving the scene without reporting the damage and obstruction. 

The 17:50 Gloucester to Warminster service is currently (as at 20:50) sat at Melksham station. It has struck something in the vicinity of Dunch Lane bridge. Both engines were initially shut down but the crew have managed to revive them and limp forwards to Melksham station. The unit from the 20:06 Westbury to Cheltenham service (cancelled) is being used to rescue the stranded train.