I've been reversing the bottom boxes for years in the spring once a flow starts. It is an easy way to cull out older frames and at least for me it seems to work. Disrupting the brood nest is a drawback if you are in an area with later frost or cold nights. Two of the hives I reversed this year lost some brood because of a sudden cold snap, go figure frost at the end of March in Florida. Of course if the bottom box is empty it can be pulled and the hive shrunk down till the extra room is needed again. If you are in an area with small hive beetles then pulling the bottom box and keeping the hive packed full of bees is the way to go. It all really depends on how much time you have towork the hives and your managment style.
Even with the brood chilling I'm glad I swapped the boxes two weeks ago, they are already full of honey and I ended up supering up the beeyard today. It has started again !!!!