I feel sorry for customer service reps and anyone else who has to deal with the customer, but your management team, or whoever, handled this whole thing in the worst way possible. The promised queue system is nowhere to be seen. Preorders are still open when you have well over 10k+ orders. You're still boasting how you're getting the best supply in the UK when it's probably not even remotely true and just empty PR speak. You're also telling your customers you'll contact them only to ignore them and go radio silent.
I understand that no one really knows anything about the stock situation and stuff, but the worst thing you can do is lie or make empty promises to your customers, it will only come back and bite you in the ass in the long run. Been there, done that.