Confusion over the 1997 episodes - Jamila Blake

I came across this set recently - I'm still looking for 1995 and 1996.
Early in Part 3 WPC Jamila Blake rejoins the Met and upsets a few people by going straight to CID. According to the dialogue - if I heard correctly - she'd been away from the job for around 3 years.

But wait a minute. I wasn't aware that she'd left. Her presence throughout Parts 1 & 2 was unmistakable. The book, 20 Years At Sun Hill, wasn't any help either.
Have the DVD makers screwed up or what?

(I've noticed inconsistencies in the early sets, for example Chris Turnham leaving, and a couple of episodes later he's still around having his suitability for the transfer investigated.
Likewise work on the new nick commences before the idea of building a new place was even proposed.)

Love is never having to say you're sober.