When to replant my hydrangea to a different spot?

http://www.mcall.com/features/home/mc-garden-hydrangea-transplant-plant-time-20160909-story.html

Majority of hydrangeas cannot handle the hot sun of mid-day! They will wilt and eventually sun will scorch some leaves. Transplant in late fall or in spring before plant comes out of dormancy. However, I grow many hydrangeas and have moved them whenever necessary. Besides shade, hydrangeas crave water thus the word hydra. Good luck as they are well worth any effort and are really quite easy to grow!!! In the fall, let the falling leaves from trees stay on plant base to protect from winter cold.

I move mine in early spring or fall.

Spring or Fall!

https://www.bhg.com/gardening/flowers/perennials/hydrangea-pruning/

I found this helpful for the care of my hydrangea!

they prefer shade /part shade

before they leaf out-while still dormant

Always water well a day before transplanting anything, to reduce the shock. As yours has not been in place too long, the roots would not have spread too far, but if they had, you would need to wrench a week before moving. Wrenching is when you put a spade through the soil in a circle perimeter, severing the out growing roots. The week time frame is so the plant can adjust to the shock before moving. You don’t want to give it too many shocks at one time if you want it to survive. Plants begin their dormancy period in Fall, so this is the best time for an established plant to be moved. i doubt yours has established itself yet, so anytime would be fine.