I check on a weekly basis all my bookings - cash and points - to see if there have been any rate changes and cancel and rebook as appropriate and have been doing for a long time.

I only ever book cancellable cash rates these days so that helps

I keep all my bookings on a spreadsheet and include the latest cancel by date in that. I do check close into that of rates have done down which works sometimes but sometimes not.

On another site I post on every now and then someone starts a thread about regular checking as though it was some special hack they have personally discovered when in reality a lot of us have been doing it for years.