I have a mature peony that needs to be moved. I can't wait till fall because it is in the way of some shrubs that need some room. Wish I had moved it last fall but I didn't so here we are. Is there any chance of it surviving? Suggestions to help it survive. Line the new hole with deep compost and rooting compound or epsom salts? Can I just cut it back after if finishes blooming?

let it bloom, cut it half off, dig it up and put it right in its new spot. Water it in and mulch. Do not plant it deep, they like to be just under the surface.

If it is a mature herbaceous Peonies and if you want more than 1 plant you can split it up...When I lived in Michigan I loved my Peonies both Herbaceous and tree...

I am assuming we are talking herbaceous peony, not tree peony. You can transplant peony in the spring. Don't wait until after it blooms, do it now. Prepare the new planting hole - dig it deep with lots of compost. Water the peony really well a couple days before you dig it up. Try to get as much root as possible.

Its in full bloom now. I think I just do my best. I had just heard they were really hard to move other than late fall.

Its really late to do this spring, fall is always best. But, as you have no option, the sooner the better.

I moved a tree peony in the spring. Several people told me it could not be done successfully. But the option was move or it was going to be destroyed. It struggled the first year. Was happy last year (the second year) but did not bloom. This year (year three) it is very very happy and I'm going to be blessed with one bloom.

As for herbaceous peonies, I have had people give me them in the spring. It has taken mine anywhere from two to four year before they bloom.

It can be done. You just have to be patient for blooms

If you wish to move it as one plant, the trick is to get as large a root ball as possible.
This is easier said than done as I move three very old ones and had to dig huge deep holes to try to get as much as possible.

Two of the three are doing OK although I think I have bad spot as they are not getting as big as they should be after a fair number of years.
The third blooms every year but is not really getting bigger and I am going to move it this fall.

From my experience it seems once they are truly established depth means little but if they are too deep when you replant, they just seem not grow and not die.
IF they are too high, you can always put more dirt on them but if they are too low it is not fun.