I'm not surprised to see more characters returning, as I suppose it just took a little longer to negotiate contracts with some cast members. Plus maybe some had been working other jobs and weren't immediately available.
I'm getting all confused with the timelines at the moment. When Byron was talking to Reece he said she was at the Sonya Foundation yesterday and with Tess on the tram yesterday, but weren't those episodes days apart? Erinsborough must be in its own time zone.
Also I see Mike was in the preview for an upcoming episode. I still think they'll kill him off, but for now they seem content with having him be on video calls. I can't see that happening long term though. I still think it's good of Guy Pearce to be the show - it's a shame he can't be in it long term but I know that's not gonna happen!