Thinking of taking a short break away in a couple of weeks. Going to book Advance tickets, but only now just found out that GA have temporarily suspended seat reservations, pending the introduction of new stock. Usually traveling on Advances on other trips, I'm used to having an allocated seat. Is this likely to cause me a problem? I mean how busy are these trains. I'll probably be traveling from London at around 10:30 am, and back in the 16:30. In first class. Thanks.