I use FGMO and smear it around the bottom boards and this has worked great keeping the ants out. I'm reapplying either tomorrow or the day after. I did a partial swipe with my finger today and they were getting thin, so I'll reapply. We had our first rain in a long time last night, too heavy, and some was washed off. It lasts for quite a while and stands up to medium or less rain. The bees stay away from the FGMO and the ants don't get in from the outside. With a SBB the bees keep them out from coming in. I've watched the guard bees bite the devil out of 'em.
As far as how long I'll need to go back to my notes and see if I wrote it down. I had better have.
With SHB I learned how to bait them in. Leave your protein patties on too long and they love you for it and start to trash a newly installed package.

As I write this I wonder if you can't set up a bait trap like the yellow jacket/wax moth traps?
David