How much longer do you think these have?

4 weeks by my estimation. That's a long flower time, but that's what it looks like to me.

In my experience this kind of difference might come from substrate deficiencies such as a stone or stick messing with the roots. Also a couple of days in seed popping might amplificate into weeks depending on the situation. I think one of the best ways to cope with this differences is harvesting at peak levels for each plant. This will also help to develop the remaining plants faster as they will have more light after cutting the done plants or buds as they are done for your preference. Keep on the great care! Happy smokes!

Looking at the pics 2-3 weeks.👍👍From The White House.