OK, not quite the cheery responses I was hoping for, but pretty much what I expected!
We are already happily tied to the area here anyway, kids are settled at school etc, so that isn’t an issue. My folks want to move now and make their own circle of friends locally while they are still independent enough to do it for themselves, and can start to look at longer term care options round here, rather than have a sudden dramatic need to move should anything happen when they are in their dotage.
We went along with their plan on the understanding that they would be responsible for sorting out their own social life without relying on us, and that they wouldn’t see much more of us than they currently do.
That said, the idea of finally (after 9 years) having babysitters on tap if we want them is not without attractions. Then I’ll be able to go and visit MrsMCTD when she is serving time for attempted Mother-in-law-cide, if such a term exists!