Is is possible to get several or any, mid cycle readings, so we can see if the insulin is doing anything. With prozinc it has probably worn off by the time you take the next preshot reading. Even if you can't do it everyday, random readings anytime during the cycle can be useful when viewed as a collection. I'm wondering if it is time for an increase, but don't have enough data to have an opinion... I would love to see a +4, +6, +8, +10 to see if there is any curve, and how low he may be going.
Why are you feeding so long before the shot? Is that just because of your crazy schedule? If not, many folks prefer not to feed during the last 2-3 hours before the "test feed shoot" routine because PZI insulin is likely fading during this period.
BTW is Mickey unusually hungry? Does he snore? Was he on any steroids that could have caused his FD?