I am surprised no one has responded so far. I can only give a little practical advise as I live in zone 8b. I would have already done transplanting if possible. But I do understand your conditions are way different from mine. But I would say Dig your new hole first amend soil if needed. When you dig get has many roots as possible. Have a tarp or something similar, to slide under rootball to keep it intact. Having another set of hands is always helpful. You may need a pry bar or a piece of 2x4 to pry under center of rootball. Once you have plant roots loose slide tarp under as much as possible with another set of hands you can lift one side of rootball to access other side so tarp is completely under then you can lift plant out set in will barrow or use tarp to slide plant to new location. I am sorry some of this may seem out of order. Several days before you plant to dig. water plant well slowly and deeply, this will help soil stay together better while digging and moving and repositioning. I have recently moved a large growing holly bush that I had only set out in a temporary location and took off like gangbusters so had to move already 8 feet high in 3 0r 4 years. So dug root ball and had to cut many roots. I had to use a 2x4 to pry up under the center of root ball because the shovel wouldn't let me reach any farther. But was able to slide tarp under and with help lift from the crater I'd dug move to an already prepared hole. I did some slight pruning to shape but ended up cutting off main leaders but it is such will make new ones quickly this summer. If you are able to get a goodly amount of roots and keep plant moist so it will not dry out you may not need to prune. But if you loose many roots prune to shape so you keep a balance of top to bottom. There are many other post on this site about moving camellias so read them and get a good idea of what you are doing and you should be successful. Good luck James Maloy

Transplant the camellia when it's dormant (before it puts out new leaves in the spring.) Keep it shaded and watered after you move it until it gets established. Good luck. Rich

the best time for your area would be similar for mine. if you are digging and relocating plants, it would be in late fall or early winter when temps are above freezing. container grown plants can be transplanted any time of the year but i personally would also plant those in fall or winter because of the lower temps and more abundant rainfall. do not plant too deeply, keeping the rootball about 1" above the surrounding ground level. it will settle over time with watering. mulch after planting. pine needles or bark are popular here.

Japonicas may suffer if they get too much sun (Sasanquas can handle more sun). Wind can also cause drooping when the leaves loose moisture faster than the plant can absorb moisture through the roots. Protection from the winds can help remedy the dropping problem. Protection from too much sun can help remedy the browning of leaves. Maintaining the soil evenly moist can help a little with both issues. Aim for 4 hours of sun or less. Summer temperatures, summer winds and lack of Spring-like moisture plus transplant shock (an affected root system) are making the shrubs react this way. In Z10, I would have transplanted them during the winter months but I understand that this is something one cannot schedule sometimes. If they get a lot more than 4 hours of sun, you may need to transplant them again. Temporarily, you can help[ by keeping the soil moist as evenly as possible; block the sun with 35% shade cloth or some other object; protect from the winds with some object. And mulch, mulch, mulch. About 3-4" of mulch. Because the area is windy, I would also maintain about 6" of mulch past the drip line. Stressed plant should not be fertilized so I would not fertilize until next year. It would be ok to amend however, if you have to tweak the soil pH, etc. Make sure the plant remains about 1" higher than the surrounding soil. You may also want to use a stake in case there are sudden strong winds.