The ticket is not valid for travel Glasgow to London and then London to Bristol.
Glasgow Central and Bristol Temple Meads are both members of the Glasgow and Bristol groups respectively.
The map combinations between Glasgow Gp and Bristol Gp are BD+CG, BD+ZZ, BD+ZZ+FK, BS+CE, CE+BS+ZZ, CE+BS+ZZ+FK, CE+ER, CE+MM, CE+NC+MM.
Unfortunately none of these combinations allow travel on the specific routeing you wish.
The closest I could find was the Sleeper from Glasgow to Crewe and then travelling the Cross Country route down to Bristol.
There was however an interesting issue that arose, specifically using map combination BD+ZZ.
Map ZZ which is entitled "Sleeper Trains" and allows you to travel Glasgow Central to London Euston via any route the sleeper happens to take and then once in London allows you to travel from London to Exeter via Reading (the map does also continue onto Penzance).
When you move onto Map BD this then allows you to travel Exeter to Bristol via Taunton.
Now if we were to ignore the fact that you are doubling back between Taunton and Exeter would using map ZZ to travel on trains that are not "Sleeper" services be allowed in routeing guide terms even though it is pretty obvious map ZZ is showing permitted routes using both the Caledonian and Night Riviera sleeper services. I can find no mention of the "title" of the map having any bearing on the validity of permitted routes but I may have missed something along the way.
A60K said:
Pretty certain no, without checking the RG. The GLC-BRI fares are not routed with a cross-London connection - £138.90 SVR. From Dumbarton there are two fares available however - Not London £142.30 SVR and +Any Permitted £161.70 SVR. That's probably the cheapest way to do it.
It is actually irrelevant whether there is a Maltese Cross or not printed on the ticket, this is not definitive to whether a particular ticket is valid via London or not.
There are a few examples of flows that both the routeing guide and WebTISs state as being valid via London and that include a cross-London transfer but in fact do not have the Maltese Cross printed on them.
The routeing guide even mentions these under Step 6 of "How to determine a permitted route"
NRG said:
The via London, Maltese Cross symbol (D ) on a ticket signifies that the ticket may be used via London Underground or Thameslink services. Unless a ticket specifies that the journey must be made via London, passengers are free to use an alternative ‘permitted route’ for their journey as provided by the Routeing Guide.
In some instances (particularly long distance cross country journeys) the Fares Manual will show an "any permitted" fare but without the via London, Maltese cross (D ) symbol. Reference to Section C (yellow pages) may show via London to be a permitted route for this journey and in such instances travel via London to include cross-London transfer would be permitted.
