Rootbound tree question

I have a pine in a 1 gallon pot... it is root bound.

I was told not to re pot it now but wait for the right season... makes sense.

Have decided to leave it grow for a few years before i put it in a bonsai pot...

If I take the root-bound tree and put it in say, a three or five gallon nursery pot... will that resolve the root bound issue now that it has more room.

Or, do I have to do some root work before I even place it in a larger nursery pot?

Any root work you don't do now, you will have to do 10 fold in the future. And on a pine, nebari is one of the hardest things to develop. I suggest starting now (during your spring repotting).

There is a chance that being in Fla. that the tree is in summer dormancy right now (?).  Pull the tree out of the pot and at least cut off the bottom 1/4 inch or so of matted and circling roots at the bottom of the pot.  Put it in a larger pot with similar soil and fertilize with a heavy phosphorus (2nd number) fertilizer.  This is a bloom fertilizer but promotes strong root growth.  Should it push out a second flush of groth soon use a high nitrogen fertilizer.  All of this assumes that the tree is healthy,  It's color should bee deep green, the needles firm and if you pluck one it should make a good snapping sound.  Also if you cut a stem off it should begin to bleed sap quickly (5-15 seconds).  If not then do not disturb the roots, put it in a slightly larger pot and fertilize with something like Miracle grow and possibly some chelated iron.  Next spring untangle the root and put it in a porous soil.  I use 2/3 Promix and 1/3 perlite.  Then fertilize heavily.  Then hurry up and wait.  In 15 years you should have a very nice specimen.