Jen,
I placed the strips into 9 hives in August and removed them 43 days later. As of this past week end all 9 are still alive. I am ashamed to admit that I have not tested for mite counts. I intend to OAV the hives on the next 40 degree or higher day. I am hoping the cluster will not be as tight and will allow better over all coverage of the bees with the Oxalic Acid. It looks like it will be Sunday if you can believe our local weather station. I am hoping that the hives are as close to broodless as they will be in the yearly cycle. The OAV should knock the remaining mite numbers down as most of them will be phoretic.
Should any or all of the hives remain alive I will probably treat them again in late January with OAV. If we have a warm day in late winter I will test for mites with an alcohol wash.
As always I should mention that I don't think I will ever know more about bees than I don't know.