What the last few days have revealed is that there are a lot of people who didn't act on club advice when the new CRM system that Ticketmaster draws data from went live.
It was publicised multiple times to make sure that you logged into account and addressed any issues if you discovered them.
From reading this forum and Twitter, it's clear that a lot of people ended being slowed down by the need to amend profile, and things that could have been done a few weeks ago.
Additionally, people wasted time having to add fellow supporters to their network that they were trying to get tickets for. Myself and my friends who were sorting tickets today made sure we were all in each others network last night so that the chap logging on, just had to click 4 tickets and get them in his basket.
With only 1350 tickets available and a lot of people buying more than 1 in their transaction (i.e. they had the correct number of ST holder fan IDs), then I'm not surprised that tickets were showing as unavailable shortly after 4pm. It it highly possible that all tickets went straight into people's baskets and the website then told people that their criteria wasn't available, especially if you were looking for more than 1 ticket, and it couldn't find them together, it would return not available. That's a wider point about the programming of the site, it should return something like "there are x tickets available but they are not together - do you want to continue".
Equally as transactions don't complete through people timing out, cancelling purchase or any other reason. Those tickets would have re-appeared for sale a few minutes later. That explains why they may have been showing unavailable at 4:03, but someone could have purchased at 4:10. That happens on all ticketing systems, as tickets remain "sold" for an amount of time before releasing back for sale.
That being said, there clearly were some scenarios cropping up that should be addressed
Read a lot about page timing out when going to pay - that is something I've noticed this season, the timer clock for completing your transaction seems to be way shorter than in previous season. I want to say it was 15mins previously, pretty sure it's substantially less than that now.
If you're buying more than 1 and needing to assign it to someone, and then go through the payment process including approving on your banking app. It isn't a surprise that some people were timed out.
I think the club need to do some "how to" guides over the close season, and perhaps advise people to ensure that they have as many people in their ticketing 'network' as possible before the season starts e.g. family, friends they sit next to at home games, their regular away day mates etc.
Does allocating priority by some form of "away points" system solve things? Potentially, though it removes the ability to 'pay on the day' at away grounds as otherwise there is no way to record who has purchased which game. It would also take a few games to start having an impact. There's also then the risk that those who can't attend as regularly for whatever reason, just sit consistently at the bottom of the points system and never get the opportunity to get to away games.
Some clubs have away memberships where you pay an amount to get 'in the queue' so to speak for away games, and then you start earning points.
If you don't intend to ever travel away, then you wouldn't buy a membership but that then shoves you right to the bottom of the list for those matches that do have potential to sell out.