I recommend putting at least a loose structure around your time to start with. It's very hard to transition from a long term full time role like that to being slightly unoccupied. What's in the structure is less important. So it's fine to have "bum around for 6 months" in there, but agree with yourself up front that's what you're going to do, so you can move more gradually from a quite structured day to a free-form one.

Something like
Oct - Dec: travel, go on holiday, read, generally unwind, make a list of all the small things round the house that really need doing, do an exercise program
Jan - Feb: do all the small things round the house that really need doing, write down everything that might be interesting to do longer term
Mar on: Explore properly all the things on the maybe list

Regards

Mark