Theory talk:Timeline - Leela

Placement of Wicked Sisters Stories
As noted, Leela appears older than the Doctor in these stories, so I doubt that they take place shortly after her adventures with the Fourth Doctor in her own timeline. That's to say nothing of how she seems to be very used to Time Lord technology at this point and the science behind it. I think it's reasonable to assume that theses stories probably take place much later in her timeline.