In fall flush. Blooms are bigger in spring.

If your rose were relatively dormant it would quite honestly be pretty easy, but in your zone it likely now has tons of tender fresh growth, and tender growth needs the (now equally tender) roots to sustain it.
I will defer to others to refute or verify my thoughts here, but if you need it done this season, *if* your weather is generally mild and conducive to pushing new growth for a month or two following the spring flush (typically when blossoms are spent and foliage is hardened off so plant can shift its focus to fruit development) I would be inclined to cut it back *then* and dig with as much of a rootball as reasonable. Ideally, your rose wants to maintain a certain root:shoot balance, so you will want to do some pruning of shoots so as not to overly tax it as you will invariably damage roots. You will want a modicum of *mature* and not baby foliar growth remaining; grown leaves puts less unreasonable demands on the nutrient flow from the roots than developing baby leaves.

I hope that made sense. Others might chime in with more practical (as opposed to my theoretical) experience.

Yah... I see you say "hot and dry" so waiting might mean more adverse conditions...
Cannot wait until mid "winter" where you are?

I've dug out and potted up roses at almost any time of the year, when they were doing poorly and I wanted to coddle them, but I haven't tried doing it when they have just freshly leafed out. I'd be hesitant to do that for the reasons that others have mentioned. Your plant is two seasons old, so it's still fairly new and should transplant better than if it was many years old. You could consider waiting until the new growth has hardened off before pruning back, and then potting up. Personally, I would take cuttings first, and make sure the cuttings are rooted before digging the original plant up. It would set you back by a season before you could remove the original plant, but the other option would be to be prepared to replace Bolero if your transplant failed.

Thank you all! It sounds to me as if I should leave Bolero where it is right now and go through this process next winter.

I just want to buy a PJP… and yes, I may start it in a pot if I can. If I absolutely can’t resist the prospect of buying another rose …

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I would wait to until "Fall or Winter". I think just spade it up all around and plunk it in a pot using potting soil or mix.

I'd definitely wait until our winter to dig out Bolero. For an alternative perspective, I had friends who moved from a duplex to their first purchased home one August, and they dug out every rose from the ground and put them in pots at their new home and lost not one. The big difference here is that you're in a really hot area (Santa Clarita, right?), and these friends are in Santa Barbara. My friends lucked out. As Sheila said above, you could just spade it out, or you could bare root it and use all fresh potting soil. I've done both in our late fall/winter/early spring with good success :-D

Susan, you are correct, I’m in Santa Clarita, high nineties today … your Oklahoma, by the way, is gorgeous.I had that rose at my old house in the San Fernando Valley, but I couldn’t bring it with me when we moved. couldn’t take it with me when we moved. It’s been eight years, yet I still miss my Oklahoma and its fabulous scent.

Sorry, Houzz messes with my keyboard.

I'm in a very different situation from you but I can tell you that I found Bolero to grow much better in a pot than in the ground. I tried several of them and they died back terribly and finally I got rid of two and moved one to a pot, where it has been living happily ever after. I put the pot in the garage in the winter. I recently took it out of the garage where it has spent the last two winters, and it looks unfazed and ready to go. I don't remember what time of year I dug it up, but it was no doubt smaller than yours.

Thanks, Nancy! I think I definitely want to put Bolero in a pot, but I won’t be doing it until next winter. Glad to hear about your success with it. I don’t face winter frost, here, but I’m glad yours survived so well.