Not an idea but a comment.
Last time the financial requirements for retirement extensions were increased, "grandfathering" was introduced. This meant that there was no increase for some.
The main condition was (if I recall correctly) you needed to have 4 or 5 consecutive, uninterrupted, extensions to qualify.
So, if you interrupt your series of extensions, and the financial requirements are increased in the next 4 or 5 years, you may need to keep a lot more than 800,000 in the bank, or 65,000 per month.
There has been no increase for 20-ish years, maybe one is due.