Hey guys
I don't have any documentation here in front of me, but one question:
Why select isolation valve to "close" at all? Departing with applicable pack switch off and isolation valve auto gives you an open isolation valve and normal pack flow until flaps are up (supplied by both engines). When flaps are up the remaining pack operates in high flow for the duration of the flight.
The thrust would not be asymmetrical and the bleed air demand would not be greater than normal.