Okay, so:
Before gamestart (like, before signups closed, before this game got underway) Ducky and I were talking about the game and there was discussion about potentially introducing a mechanic in which a town member would "swing" to mafia on a later night, so this could be what happened (i.e. a preset, unknown event that none of us were aware of until now, or something along the lines of rooms exploding idk)
I feel like Ducky would probably tell us at the beginning of the game if this was a thing though so this is probably a complete shot in the dark, but if this is actually an option that is ... on the table. I have no idea if Ducky can confirm Random Conversions aren't actually a thing, though
The only other options that I can think of is that someone decided to bail from a room for whatever reason last night, but I'll also assert like Kiyoko that I did the thing
e: to reply to drandahl --
Also, would Lux warn us? If she honestly thought she might get converted, wouldn't it be in her best interest to prepare for that case?
If nobody was converted, there would be no need to justify her actions.
If she flipped, she'd need to be careful not to incriminate herself.
wrench in this plan is that Lux explicitly said she got the item from the brig and used it on herself, and therefore:
a) given her impassioned feelings towards the mafia I doubt she would deliberately peel away from the rest of the town if she was lying about it and open herself up for conversion
b) if she wasn't lying then if she were targeted she would be Dead