Re: have you switched from screened to solid bottom boards?
Abbreviations... Solid bottom boards were the norm for decades (could say a century's worth of'em!) with no mention of screens...they were just called "bottom boards". Then came the screened bottom boards which were naturally called..."screened bottom boards". To me, BB means solid bottom boards and SBB means screened bottom boards. If I see "BB" I take is as a bottom board with no "Screen"...."SBB" has the "Screen" added. Of course in smaller circles, meaning my mentor and me, we refer to our screened bottom boards as simply bottom boards because that's our normal bottom board...I do have a few solid boards, but if I mention them to my mentor I refer to them as "Solid bottom boards". Beekeeping is local.
Warning: Rookie beek...take my postings with that grain of salt you keep in your pocket.