Someone edited Wikipedia as saying she makes her final appearance on the 5th but then it already showed Glenda and Jacks reaction to their bodies without actually showing anything?

Maybe she'll appear to Jack as a ghost lol

Probably used to convince people she doesn't die. Someone said they did that with another characters death.

Unless it's like video footage they use of when Ronnie was alive, a bit like they did with Heather.

Drowned bodies look grim ... bloated and discoloured, so I doubt it. You could tell from Glenda's reaction that she didn't look peaceful.

Wiki entry was amended based on Official BBC Episode Guide/Cast List