When she was defeated as a minion and sent back to the squeezer row she gets estrus I noticed while experimenting with her that it was broken and never actually activated the next turn I'm guessing the part where it removes all effects except for partner when she is resummoned as a squeezer must have been overlapping with that. I haven't tried the bug fix yet but I would wager it was that.
Negative, that bug is new to the full release and wasn't in the dev build. The raw translation is as follows.
-If "Kurotetsu and the Incubus of Selfishness", which is a guardian of two companions, is targeted, it will be sent to the discard pile.
That's the raw translation for Iron Succubus. There are two possible interpretations I can think of.
When she was taken control of with Hypnophone, swapping, whatever, and got destroyed by battle, she would return to her original owner's side of the field as normal. Potentially she is now sent to the graveyard instead.
When she was targeted with Mutual destruction, she would return to her owner's side of the field, but if there was a second Mutual Destruction, it would trigger again and send her to the graveyard, which doesn't seem... intended.
Again, unknown what it is, haven't tested enough.