If the dirt is similar where you are moving and the clumps don't need dividing, then by all means disturb the plant the least by including dirt.

"........I'll only be able to wait a week or so after bloom to move them........."

After bloom is perfect timing to dig, shake off the soil and toss into bags for later treatment. At this point I'd begin labeling leaves, or bags. That is always more time consuming than I expect.

Hope you new place has good soil :-)

Because I live in such a short-season climate, I necessarily have to do my digging and dividing immediately after bloom is finished. I don't think it affects the plants any more than digging and dividing a month or two after bloom.

Laurie

I moved in March of last year & just carried my dug up Iris clumps with dirt snuggled together in plastic flats lined with newspaper.
Most bloomed last year & this anyway!