Hi
As Bob correctly pints out, the quick and dirty Imperial Valley divide may leave you with a lot of queenless hives. But no doubt, fewer than you had originally.

A slight modification would greatly improve the technique. Order queens and a few days before they arrive, get the queen down to the first story (shake the bees off the combs, or whatever) and put in an excluder between 1 and 2.

When the queens arrive, smoke the bees up into the second and move this off to a new stand. Introduce the new queen to this part.

The old hive keeps the old queen and most of the old bees. The new hive gets lots of brood, young bees and the new queen, which will be readily accepted by the young bees.

PB
New York