I have screen bottoms with thin sliding plywood drawers that seal the trap area below the screen.
My hives are in full spring build up from Eucalyptus and are a cohort is busily fanning at the front entrance.
I thought to slide open the bottom drawer to permit increased circulation. I had some moisture and mold accumulate on the drawer during the winter quiet period.
I am concerned that opening the screen drawers will simply short circuit ventilation inside the hive. The bees fanning at the front entrance will be drawing air from the screen and short circuit any circulation within the hive, defeating the evaporation the bees are working to accomplish.
I am in a moderate coastal climate, temperatures in the 70's, no higher, with high humidity. Reduction of nectar to honey likely requires a lot more effort here than in hot dry climates with higher evaporation, hence my concern.
Any guidance here-- on hive management to maximize evaporation rates.
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Let the bees do the job. You need not maximize anything.
Another important thing is that at night hive is not too cold if bottom is too open.
I look for number of fanners, is the ventilation proper or too cold.
If the hive is too hot, bees make clusters outside.
In my climate, which is considerably colder than yours, I leave the screened bottoms open year 'round. The only time I slide in the board is when I'm taking mite counts.
My SSB's are left open year round as well. I have a small (1 1/2") upper entrances a well as the regular bottom entrance per hive. The bees will propolize the upper entrance all but closed as winter approaches. They mostly leave a hole the size of 2 bees in the propolis. As Spring approaches they open it back up. A SSB with an upper entrance allows for great ventilation. When the flow is on they can get to the supers faster from above and they cure more quickly becuase of the airflow. Sigh,.... I'm thinking of how good they smell when they're curing the nectar.