Now that the bullets are pulled do I need to resize the cases or just put the powder back in?

I was working up loads for a 22-250 a few weeks ago and the top levels I had loaded would have been too hot. I pulled them, reweighed the powder charges and seated the original bullets with no other prep. With two bullets and seven different charge weights, four shot groups went from .35" to .85". Only three groups were more than .65".

I usually size the necks to restore original neck tension.

This here.^^^^

Just reseat without sizing

http://www.24hourcampfire.com/ubbthreads/ubbthreads.php/topics/8805098/1

YES

I've done both (resize and not) and can't tell any difference.

Same, although it only takes a few minutes to run through a neck sizing die so if you're worried about neck tension then the solution is easy.