Have to agree about keeping the grey matter going, that's why I FISO.
Plenty of people 'retiring'* at other NSL units so there should be vacancies.
*They may even be offered 'inducements' to retire early if they're at the top of the salary scale; I know of one who went this way, said he was made 'an offer he couldn't refuse'.
My old unit seems to be constantly short of staff, always having to bandbox positions.