Update:
Just got a second opinion on the source of the oil leak. Turns out it is not the main bearing seal after all, but appears to be coming from one of the turbo's pipes... (wonder if the turbo overboosting 1.2-1.3bar when the actuator pipe was removed has anything to do with this..

)...
The oil is leaking from underneath the turbo somewhere, onto the sump, this made it look like it is the main bearing seal....
Will take the bakkie in on Monday, they will steam clean and then pinpoint exactly where it is leaking.