For PAL according to their current rules you can only play 1 year up so K can play up with 1st. K can’t play up on a mixed 1st-2nd grade team. 1st can play up with 2nd etc. etc. Only wrinkle is 2nd graders can’t play up with 3rd grade. So would have to repeat 2nd grade team again. They consider the younger grades as the development league and 3rd grade as the first “real” league. So according to their safety concerns 2nd graders can’t play up with 3rd. After that year though you can then play 1 year up again after that.