Why offer advanced ONLY on the train with an unreliable connection?

[whole diary]

[grahame]

It wasn't the first time last night ... delays to the 17:45 off Paddington to Swansea, and the TransWilts connection, which is allowed 8 minutes, misses at Swindon.  For passengers to Trowbridge, Westbury and Warminster, this typically results in a late arrival (assuming everything else is on time) of around half an hour.  For Dilton Marsh, you're looking at 2 hours, and for Melkskam there's no other connection, and you end up with a taxi or a wait for the late bus.

Question ... why on earth are advanced fares to Melksham ONLY offered on the 17:45?   It's a tight change at Swindon which results in frequent missed connections at great expense.   Why not offer advanced fares on the 17:30?
*) Much better change - Chippenham (Same Platform) rather than Swindon
*) Much less likely to fail to connect, so saves First on taxi fares
*) Much less stressful for the traveller
*) For people for whom a short journey is critical, there's better fare differentiation.   Cheaper is a bit slower (and that's not going to worry people who are price-driven)

[stationstop]

Grahame,

It might be possible to do that combination on an earlier train. It's possibily a limitation of the booking software. Have you tried forcing a longer connection time?

Very often this produces results.

[Trowres]

Hmm, on the Nationalrail site, allowing extra interchange time has a minimum half-hour increment, so it puts one on an even earlier train than desired. However, using the "Exclude interchange" option to avoid SWI^» (Swindon - next trains) worked (and also showed the alternative route via Westbury).

Whether or not the TOC^▸ (Train Operating Company) booking engines replicate this I haven't the time to check.

[JayMac]

Using the 'text only' versions of WebTIS booking engines, which now include FGW^▸ (First Great Western)'s, allows you to specify 'extended station change times'.

http://tickets.firstgreatwestern.co.uk/gw/en/JourneyPlanning/Wizard/StationSelect

Looking at a specimen journey from Paddington to Melksham on 27th November I was able to get the booking engine to offer me an Advance Purchase fare on the 1730 changing at Chippenham.