I definitely think if the intention was to promote someone to the 5pm permanently, it would have been done already, as mentioned, there's no point in delaying that. I think with Paramount trying to cut costs, keeping only 1 permanent anchor on the shows (Kristine) might be a way to save money (?), at the expense of viewers having to see a different anchor next to her at 5pm depending on the day. Kristine seems to be permanent at 6pm/11pm, and it was mentioned they are moving towards solo anchors. Originally she used to, but I don't think Kristine does the 8pm anymore (it seems to be Allen Devlin or Dick Brennan most nights).
I think the theory of keeping the seat open for Maurice is interesting and I could see a situation where the Evening News removes 1 of its co-anchors, also to cut costs.
On the weather front, Lonnie has now re-added the 6pm to his schedule, so he seems to do everything again weekdays, except for the 8pm; which has been Vanessa or Craig Allen. I do wonder how they will add Scott Padget into the mix.