I vaguely remember, that on ground the the APU bleed switch in on and on ground does indeed open the crossbleed valve. It’s been a while, though.
Still, since you will have to set brakes first in order to be able to then increase power to have enough duct pressure for an engine-friendly start, it seems sensible to at least consider entering the supplementary procedure. This being mandatory or not may be a company issue.
Also, APU auto-shutdown does trigger an ECAM caution, or not!? Surely one has to take care of this first!?
Last edited by boeing747430; 8th September 2024 at 22:03.