You are following SLGS, so that would indicate that you hold the dose for 7 days, then do a curve, then assess the dose.
Currently, you don’t know how low the current dose is taking Chloe, so I would try a few things first:
1. Get a +2 on each pm cycle. If the +2 is the same or less than PMPS, that can indicate (but not always) that it could be an active cycle where you may need to get a further test on that cycle. Many cats go lower at night.
2. Try and get a mid cycle test on each am cycle. 1/21 is a potential example where there may have been a drop and resulting bounce?
Hope the drained abscess is healing nicely?