Great Western Coffee Shop

Noticed yesterday that Cornish services were messed around with a signalling problem between Plymouth and Penzance, with disruption lasting all day.
Unable to remember if there were problems on Saturday or not.
Today, journeycheck is showing
04:58 Penzance to London Paddington due 10:29
04:58 Penzance to London Paddington due 10:29 will be started from Plymouth.
It will no longer call at Penzance, Redruth, Truro, St Austell, Bodmin Parkway and Liskeard.
This is due to a fault with the signalling system.
Will be formed of 5 coaches instead of 10.

Reduced length trains in C-19 times is understandable, but more disruption today with a signalling problem.

I take it the problem is between Plymouth and Liskeard, as from Liskeard down it's all manual boxes.
Seems to be taking a while to fix.

Can't help wondering if the failure was East of Exeter, it would have been sorted a lot earlier?

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.

Indeed ... but I don't think it's so much the location as the quality of what needs fixing in the first place (modern with spares handy, or old, no spares and knackered) and the priority put on it too.  "The Melksham Line" as you name it :D has (my understanding) excellent permanent way for most of the route, allowing for high speed and heavy trains, but signalling / comms that is very thin an old. 

Putting aside the cable issue last autumn, the line was again closed for a period on 24th January because of worries that the points at the end would get stuck with snow and ice, and that being a concern unique to this line right across the whole area. Not the first time this has happened, either.  And the signalling headway must be one of the longest around; I know it's single track, but not even provision via an intermediate to have two trains following at less than quarter of an hour interval!

Looking back at Cornwall, I wonder if people work(ed) in shifts around the clock to fix the issue, or knocked off after a full day and came back refreshed the next morning to carry on ... I have seen both approaches taken depending on the importance (not the county) of the line ...

There is legislation that covers the maximum working hours and the minimum time between shifts for safety critical work.  Signalling is such an activity ever since the Hidden recommendations after the Clapham crash.

Where possible another team will be brought in so that round the clock work can be done but this will depend on their travelling time, as travelling is classed as working time.

Speed of repair is important but doing it safely is more important

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.

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!  :D  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!  ;)