The expire after a year only applies to non status members

There appear to be varialble reports on book and cancel extending miles as an approved extension method.

Personally I'd rather spend a few thousand points on a magazine or charity donation than take a chance on a redemption.

Though of course they could book something for the far end of the booking period in the hope that they then have a 'proper' earning booking in the next 11ish months.

This page has some options https://www.ihg.com/onerewards/conte...aintain-points