My suggestion would be to let the females hold to term for the first couple of times. So that she learns what to do. If you were to strip now they would always expect you to stip and then maybe just swallow or eat the eggs.
Also try not to remove the females like ryan said, it makes things complicated when you want to add them back into the colony. Things may go wrong, but given that they are duboisi it wouldn't be that bad but why take a chance?
I usually stip after 2 weeks but longer you wait the lower number of fry you will get but they will be stronger and better.
When it comes to tropheus take it easy and don't complicate things. They are alot hardier than what people think