Re: Pellicle...here today gone tomorrow
First ask yourself "what is pellicle?"
Mostly bretts (and other oxidative microorganisms).
If oxygen is restricted at the surface or if the pellicle becomes so thick that cells at the bottom of the pellicle do not interact with available O2, the cells may flocculate (a CLOSED starter for instance will have more cells on the bottom of the container than on top). This is evident in your brew now that CO2 is kicking up again. WHy is it kicking up? God knows, mixed fermentations are so complex. You can have cells dying off releasing nutrients and other populations feeding off of that.
<<But I was under the impression that when the pellicle disappears you're ready to bottle >>
I don't know about that - my pellicles are appearing when I want to bottle!