None of the East Coast long distance operators behave consistently well when disruptive incidents occur, sadly, and GC is probably the worst in this area.
If there is a later GC train that day,
but it would incur a delay of over 60 minutes at the passengers destination to wait for it, then GC should arrange an alternative, at no additional cost to passengers. If GC fail or refuse to do so, a customer has the right to purchase a ticket for such an alternative (if they are able to do so) and GC are obliged to refund the customer the cost of the more expensive ticket. GC cannot simply refund the cheapest ticket as that is not acceptable.
If there is no later GC train that day, or if the customer would otherwise be stranded (e.g. they may be relying on a subsequent connection, which a later train would miss) then the customer can rely on Condition 28.2 of the National Rail Conditions of Travel; this obliges any operator in a position to help, to do so. This includes LNER, even if LNER don't want to. If LNER have a problem with this, they need to take it up with GC using whatever means at their disposal. Customers have to be conveyed and cannot becone victims of any disagreements between the relevant TOCs.
As for GC's behaviour on Twitter, it is disgraceful and has been rightly called out.
Someone sent me GC's policy regarding disruptive incidents, which sadly GC do not consistently adhere to:
Note the use of wording such as "
ensure passengers reach their intended destinations." and "
they will not be required to purchase a new ticket, upgrade their ticket, or pay an excess fare"; this all sounds fine in theory, but in practice they are not infrequently found to behave differently.
GC really do not like it when anyone informs GC passengers of their contractual entitlements, and therefore GC has taken the decision to prevent anyone replying to their tweets. However they cannot stop re-tweets.