Mr Thant wrote:
What are people's experiences buying unusual or long distance or
Railcard-discounted tickets at NR stations where the ticket office is
run by LUL? Also, any luck getting Railcard-discounted Day Travelcards
at ordinary LUL stations?

Not good. Kentish Town is a particular nuisance as they can't dispense
return tickets for NR trains that actually stop there.

ESB