19 pax on and off with experienced crew for L2 (and most likely 225 therefore) has historically been 10 mins and totally agree it depends mostly on baggage and how much refuelling (if any) which will stretch this time by at least 5 mins owing to the 'convenience' of onloading bags.
If you add life threatening danger, i suspect a huge chunk to come off though
The ERPs should reflect a de-manning procedure though, it is a very common risk which the operators address. Check in there. Would be interested to hear what they say. I'll check mine now.