surely thymol treatment should be on a six week regime, so that it catches mites from two full brood cycles which should significantly reduce population of mites prior to winter. timing of treatment should be by season, not calender. I have not done apivar yet as bees needed a super to stop them building comb between crownboard and roof and filling with nectar. Double brood with Queen in third season never any sign of swarming always given them plenty of room in advance. Very fortunate in my location, within a short distance have canal cutting, railway cutting, huge cemetary, millenium green, four allotment sites, lime trees in all the streets. Garden hive last year 138lbs. This year 90lbs so far, two supers yet to extract. I am tired of it.