As you can see, there are many things that can effect variation in a Parrot's stool. It is also important to know that it can be in the last days of the application of a medication that changes are be seen. Depending on the bacterial, it can take very near the full treatment schedule to have a notable effect. Seeing that it is Tuesday, there is still 3.5 days of treatment remaining.
It is also, possible that another form of medication maybe needed. The good news in that your BB is under the watchful care of a CAV. Although, we are living in an age of near wondrous medical care, there is still much unknown.
FYI: I will be sending some warmer weather your way! But when you start feeling heat, don't tell me its too hot. After all the controls are a bit outdated with only two choices Cool/Cold or Warm/Hot.