Thanks to those on here with the advise on paper passports, I called the 119 service this morning and received clarification.
The bar code on the document is scanned at the venue, and there is no expiration date at this time, only the date of issue is required to be shown on the document.

The App constantly renews for four weeks, so each time you log in it shows four weeks from date and time of log in, I'm guessing this is a security measure but you don't have to do anything to renew once installed.

From 15 December NHS COVID passes are required to get into nightclubs, other late-night venues, indoor events with more than 500 people, outdoor ones with more than 4,000 people and any event with more than 10,000 people.

That last line should mean that Covid passports will not be required for any game at BV, as our current capacity is well below 8,000. Leeds Rhinos and some football clubs are currently restricting their capacity to 9,999 to avoid passport restrictions.Therefore I can see no reason why anyone should be put off buying a season ticket, the more the merrier

As far as I’m aware, seating and hospitality are not yet in the equation for passport requirements.
According to recent documents we have 1,500. North Stand, 2,293 West Terrace, 2,899 East terrace/stand, of which 1,382 are seats, and hospitality for 500,
Only standing spectators are required Covid passports, and it’s my guess Trinity will have a standing capacity of 3;999. Seats 1,382, plus 500 hospitality, we will have a 5;582 capacity that will not require Covid passports checks.
I think in the current pandemic climate, that figure is unlikely to be reached for the majority of our home games. Disappointing I know, but at least those who want to attend can do so without the fuss of passports checking on the gate.

Had to do all this for challenge cup final this year