The simple (and legal) answer is: Any point I care to choose. The sensible one is very much a mute point and as you see above, very open to discussion. But given no other information I'll carry on with Plan A until my colleagues in the cabin suggest that they may soon lose control or that a diversion might be sensible. Then, depending on what is beneath me, an en-route diversion may be started.
However, rest assured, anybody who has interfered with (and these are the words) "the safety, conduct or good order" of my flight will be arrested on arrival and I will insist that they are charged with such offences and I will appear in court to testify.
PM