SVH fares are also available from Assertis sites, as well as Raileasy and Trainline. They are only available online, as the (IDMS) description states.
The rules are:
- can only be bought online
- can only be bought in conjunction with another single as part of a return journey. The other single must therefore have the same origin and destination (the other way round of course), the same route code and the same status code (adult / child / railcard)
- the other single can be standard or first class
- the SVH can be for either the outward or return direction
- if the customer selects an SVH for travel in each direction (it is possible) then the customer should be sold an SVR instead
None of these conditions of sale (they are not restrictions, as someone else said) is supported in any fares data, so TIS have to manually implement these rules. This is also why BRfares is unable to distinguish them from other tickets (unless some manual info is added).
Virgin Trains used to do 'accreditation' of online TIS (on top of RSP accreditation!) to test the correct retailing of these. I don't know if they still do.
There used to be East Coast and (briefly) EMT equivalents. I'm not sure if they still exist.
They should not be sold through on-board machines or stations.
VT introduced them principally to cater for customers who knew what train to London (or elsewhere) they needed to get (because of a meeting for instance), and could therefore buy an Advance for it, but wanted some flexibility for coming back, and therefore couldn't buy an Advance. As SVS tickets were only £1 less than SVR tickets, the half price SVH was introduced.