Apically dominant trees are genetically programmed to 'spend' somewhere around 2/3 of the energy/food they create in the top 1/3 of the tree. If you want strong lower branches that aren't a hair's breadth from being shed on trees that show strong apical dominance, especially when the trees are grown indoors, you'll need to keep pruning/ pinching/ partially defoliating the top of the tree to direct energy flow to the lower branches and to provide the lower branches with enough light and air movement to keep them from becoming weak or being shed.
If you provide an image of your tree, I can probably get a better sense re what needs to be done.
Though it sounds counterintuitive, I'm thinking you'll need to plan on doing a hard pruning around next Memorial Day unless your lower branches are well branched with second and third order branches. The goal of that is to ensure you have branching and foliage close to the trunk. If you don't make sure that occurs soon, you'll need to write those branches off or prune them back severely at a later date. Reason: If you have a long branch low on the trunk, most of the foliage will be concentrated near the end of the branch. It's pretty much futile trying to force back-budding on that branch unless you cut it back severely; and then, you'll need to prune higher branches back very hard as well to ensure it gets the light and air movement it needs. It doesn't make sense to allow your tree to develop now, then be forced to cut off half to 3/4 of the canopy to ensure survival of the lower branches.
In all honesty, if your intent is to keep the tree in a container you don't even need to think about anything at this point but the lower 3-5 branches. Since the tree is programmed to spend it's energy in the top 3rd of the tree, you can grow a top anytime - no problem at all, as long as you can keep the plant healthy.
You can see how I have actually removed the top of the tree above to concentrate on the 3 lowest branches. The thin branch at the top, with wire on it, is the future leader.
Here, ^^^ the tree has been allowed to grow for another year.
And here it is again ^^^, starting to take shape, immediately after a repot and another hard pruning. You can see how easy it is to grow a top any time you want to.
Al
