Extracting a frozen implement jack

Customer asked to have about 25 acres bush hogged on Monday. We have a snowstorm changing to rain coming Monday night. Ground is frozen, so good cutting conditions Monday during day before storm comes Monday night and ground turns to mud again. Pretty good paying job and money is tight.
Went up to barn and discovered my bush hog sank 4" into the mud and froze SOLID into the ground (single digits for 2 nights here). I'm usuall good about putting a board under it, but that's another story.

I have run a few scenarios through my mind on how to extract it. I didn't know if I cranked jack all the way up to highest point, would it then allow me to lift bush hog out of the Jack with a tractor loader and a chain? Or do the 2 pieces of the jack stay together even when cranked to the top? (I think they do).
Any other ideas? I'd rather not destroy the jack.
I'm afraid if I don't cut it now, we'll have mud till regrow the starts in late March. Then they won't want it cut and I can kiss the payday goodbye.

Extracting a frozen implement jack