I'm in the Atlanta area and keep roses in pots with no trouble at all. I keep them under a flowering cherry tree so they get dappled sun. I keep them close together for ease of watering and to keep them from blowing over if it gets too windy. If I'm concerned about a cold winter night or few days, I'll pile some dead leaves on and between the pots and I have never had any trouble. If your weather in your zone 7b garden is anything like mine in Atlanta and if the plants are big enough (RU usually sends things that are), you could go ahead and plant them this fall. If you want to wait, you can do that too. BTW, I really like Devoniensis as well. Enjoy.

Sometimes as roses grow they send out long canes that are what the rose is meant to be in height. Sometimes they send longer canes that that even. I usually call this a “monster cane” and I usually cut it back (but I have a neverending growing season so I can afford cut a cane here and there). New roses do this as they get established but most of the time all roses get around to doing this at one point or another. Its as if they like to send all their energy into one big cane at a time on random occasions. This happens a lot in warm climates where the growing season is long and very appealing to the rose. You can leave it and let it grow (and wait for the rest of the rose to catch up) or you can cut it back so that the rose looks more uniform. It’s completely up to you. If you are in a cold climate where the rose will die back at the end of the season then you would prune anyways and end up cutting the cane regardless. If you live in a no-frost area, you can keep the cane and wait for the rest of the plant to catch up to it (might be a long wait though). It won’t harm the rose either way, but if you cut it, it can put more energy into growing other canes, and you may end up with a more well-rounded bush. Its more about aesthetics than actually harming the plant. I usually cut it because it bugs me to see one cane out of whack (but I always wait for it to bloom first).

I just got some rose bands, most of them are old garden roses, some of them have to live in pots forever in my "ice garden": Gloire de Dijon, Secret Garden Musk, Souv de la Malmaison, Souv de la Malmaison Rouge, Grandma's Hat, Xiang Fen Lian, Sou.d' Elise Vardon, Vick's Caprice. I saw a lot of Julia Child at Home Depot today, $14.99 (1 gal) and $24.99 (3 gal).

The biggest issue is keeping them dormant until spring because if they start growing in fall, they won't always have enough energy to grow again in the spring. So it works best with roses that understand dormancy and are going to trigger from something other than warmth. Given that, you may want to skip the hilling up.