I did it both ways for the past 4 seasons and got the same results from each way. I have an ARS rack that I do a night drop on and a bunch of reptile basics racks that I keep with a constant temp. Both ways gave me about 75% of the girls giving me clutches. I also drop the ambient in the room to 80 from the usual 85.
I start pairing late October and do the drop then. March 1 I bang the temps back to normal and put the ambient temps back also.
I believe it the light cycle that has most effect on them anyway..