I got there at 9:30am on Thursday. Got in almost instantly when the doors opened at 10.
There was quite a lot of choice for adults and kids at the start. Pushed my luck and went back last night and it had been gutted. Mainly XS and XXL stuff left and a bunch of 7-11 year old merch - but not as much as the first day by a long way. Shedloads of white Mens shorts, but no other colours.
Probably not much worth getting now.
Some kids mini kits for a tenner, older kids shirts for £10-15. GK kids shirts still £22.50 though which is a bit high I thought.