Dwarf Mugo Pine Repot?

Hello,

I was given a dwarf mugo pine and placed it in my greenhouse until I had time to take a look at it. I think it has good potential and it looks healthy and vigorous. The tree is in a 3 gallon nursery container and it looks like the tree is at the point where it could be transitioned from primary to secondary development. My plan was to repot this spring and not style for one year to help the roots recover.

When I was teasing the soil (nursery mix) away from some of the lower branches being covered by soil there were dense (and relatively fine) roots right at the top however, when I looked at the drain holes the soil was basically muck and I did not see/feel any roots by them and am starting to think the tree was up-potted on top of significant soil mass.

My concern is if there are no roots towards the bottom of the container, and with significant moisture just sitting there, will this cause root rot and hurt the tree before I repot this spring? I’m new to bonsai and this is my first pine - and pines seem…hard even after watching most of the pine videos. Is the best plan to repot in the next month to address this concern or leave it until February?

Thank you for your time and help!

Ya. Wait for Feb/Mar… It’s way late now to trim…
Then, Do a repot (~ 2/3 soil removable) into friable soil(bonsai soil) and put it back into your greenhouse until soil temps are above ~45F.
.
Mughu are forgiving…
Then in the fall,(if it’s doing OK), clip EVERY terminal bud. Forces back budding … {in my opinion …}
.
I did the above on several fall purchased young Mughu. They are looking great…
K

Thank you for the help good sir!