In addition to the problem of post-dated (or otherwise) railcards there’s also an issue with those approaching expiry, as currently they can only be renewed within 30 days, while tickets are available for 12 weeks. Even in the current customer-unfriendly environment I don’t see anyone from the industry saying you should buy the second one early, they’d be laughed out the room… but obviously it defeats the ‘avoiding fraud’ objective if you allow future tickets to be bought with a railcard that will be invalid by then.
And if a TVM needs to conduct live validation, you’d also need a workaround for cases where the API goes down or has a latency issue. The answer can’t just be go to a ticket office as there aren’t many of those any more. In the air industry, if the (Amadeus-hosted) frequent flyer server can’t be accessed to validate FFP status, BA will still sell you a ticket with the field blank - you’d need something here too unless (haha) you can guarantee 100% uptime.
I suspect it will be a pop-up, similar to the annoying one currently that shows ‘refund conditions are changing next month’ even when you’re buying a ticket that’s only valid for immediate travel. But who knows. If - and it’s a big if imo! - they do try to be smart, I’d suggest using some kind of NFC/RFID option rather than QR codes, as all TVMs have contactless pads but few if any have barcode scanners.
Either way, I’m glad the trial will be on someone else’s patch and not mine.
On the delay repay changes, if it drags XR into the equation at last, it will be a good thing. Currently it’s an absolute nightmare chasing anything from TfL.