More problems come from re-potting bonsai pine’s too early in the year than almost any other situation.
A pine grows very differently to most other species, and indeed re-potting techniques for same should be carried out somewhat differently to those other species.
You should be looking to re-pot middle to late spring when candles have started to form and tiny needles can be just seen forming within the candles. There are exceptions of course but this would rely greatly on your post re-potting care regime. With larger bonsai, post care is difficult at best due to the size. A full re-potting article for Japanese White; (Pinus parviflora pentaphylla) will be covered towards teh end of April, beggining of may.
Fully detailed suggestions with pictures will be included at that time. Also a Scots Pine (Pinus sylvestris) will be covered at the same time; both wild and grafted dwarf varieties.
It is helpful for re-potting if the soil medium can be kept towards the dry-side. In addition the more water you give at the start of the season the more the tree will look for. A bonsai technique has therefore been implemented here, to lessen the amount of water being introduced to this 160 year old 300lbs brutish White Pine.