Got a reply to the second email I sent to National Rail. Looks like there are moves afoot to rectify the discrepancy between physical and digital expiry dates. Here's their full reply:
Hi Peter
Thank you for your further email.
I sincerely apologise for any stress you’ve experienced due to my colleague’s previous response. Before I address your concerns, I would like to advise you that the customer experience is important to us; therefore, we have internally addressed the feedback you have shared with the advisor who responded to you previously.
I completely understand that you’re unhappy with the functionality of our technological system which renders Digital Railcard invalid the moment the expiry date commences. I further accept your dissatisfaction with the difference in the validity period of physical and digital Railcard.
We agree that Digital Railcards should be valid until 23:59:59 on the day of expiry, so that customers have the opportunity to make optimum use of their Railcard. You will, therefore, be pleased to know that this issue has been raised with the Railcard Technical Team and with whom we expect to expedite the rectification of this error.
Until we’re able to resolve this complaint, may I politely suggest you accept our following suggestion. If you’re planning to make any journey on the expiry date of your Railcard, then please purchase a full-fare ticket. Once you’ve completed your journey, please send us a screen capture of your purchased train ticket, so that we can reimburse you the difference in the fare.
I appreciate the time and effort you’ve taken to bring this matter to our attention, and I’m grateful that you’ve given us an opportunity to help you.
Kind regards
Georgy Oommen
Supervisor - The Railcard Help Team