It sounds like you are in the same boat as me. I purchased a RH in late fall and kept it in a pot all winter stored in the garage. I had good intentions of planting it out in the yard, but just didn’t get around to it. The tree began to bloom in February in the garage since the garage was not quite as cold as the outside…way ahead of what would be suitable to survive outside. I had to keep the tree indoors from February through late April. Fortunately, we ended up with two peaches that ripened up nicely in June!
However, I don’t believe the tree is all that happy living in a pot. It’s been transplanted to a fairly large pot as well to live in for the time being. I’m planning on planting it in the ground this fall once it’s dormant. I haven’t fertilized the tree at all since it may be a little stressed in the pot.
On the upside, if you do keep the tree in a pot and store it in the garage for winter protection, it will probably break dormancy again fairly early. However, it will look very nice while in bloom if you have a suitable place in the house for it with enough sunshine.