Nobody should be called up.
Dickerson should stay there until the end of the AAA season where he won't miss any at-bats.
The others should stay at AA until the rest of their season to continue their growth. There's plenty of playing time left in the Winter Leagues for the AA players and AAA will be waiting for all of them next season, including Cumberland. Stubbs should begin next season in AA, no matter what.
In September, Dickerson will be sharing playing time in the Outfield in the Majors.