Very cool plate- love the long tentacled ones.
You should separate the brain from the plate a bit more. Once they have trouble start, it could be too late. You wouldn't want either to be injured or to die.
I have "heard" that sometimes when a plate dies, if you leave it alone for several months that individuals will emerge from it and seek out a new spot. Its sort of like the mother starship dies but some colonists survive. . . . . . . . I don't know if that is an old wives tale or true. I just thought it was interesting.