I'm in kind of the same boat as Dave.
As a softball umpire in AZ, i'm able to work almost all year around.
Since I only call HS girls
VB, that's only a few months a year.
Our HS officials are required to attend and officiate at one pre-season scrimmage a year. Most of the HS around here participate in one, so there are several to choose from. I use these scrimmages to knock the rust off and get in the swing of calling
VB again.