The only reason a Platium's (or better Diamond) points would not expire is that to be any status requires recent stays. The exception to the stay/status is all the recent comps.

Life time points are not awarded.

At to special status for total points, I have 300,000 and it has not give me anthing outside the program. My wife has over 500,000 and she has not recieved anything outside the normal program either. There is nothing published that I know of for a 1MM point special status.

As a side note. AS no longer even states you mileage since enrollment on its statements! I think some have backed out of this concept as is get more "crowded" over time.