Answer: If you can dig the soil (meaning it is not too frozen) you can lift the shrubs and replant immediately. Take as much of the root ball as possible, and trim back the tops to compensate for any root loss in the digging process. If you can replant them immediately in their new permanent location, that would be the best thing to do.
If you must keep them temporarily, the best way is to plant them temporarily in say a vegetable garden area that is currently empty (your own or at a friend's house), and then transplant them as soon as possible to their new permanent location.
Keeping them in a pot would be my last choice of options for several reasons. It is difficult to keep the native soil in the rootball evenly moist when surrounded by potting mix, and it is difficult to keep the roots sufficiently insulated while in a pot as opposed to buried in the ground. If possible, bury the pot in the ground to its rim or pile mulch around it to insulate the roots from freezing weather. Again, plant it in the ground as soon as you can.
Surprisingly, it is actually better to plant them very early (as soon as the soil can be dug) than to wait until they have come into active growth.
You will need to treat the transplanted shrubs as you would any newly planted shrub, taking care to water regularly to keep the soil evenly moist (during the growing season and through fall until the ground freezes) while it becomes established again.
Good luck with the move.
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