Given the vast number of extensions that DL is granting, I tend to think the extension is foolish.
The bloated elite pool means two things - you are essentially trading 100k miles for four GUC's which you may or may not be able to use. And that DL won't adjust the diamond MQD threshold until they know how many people hit it organically. The comically low threshold to extend and the amount of time they allow tells me that they want us to extend rather than convert to RDM. In the interim they won't modify the MQD threshold much if at all since many people will be on extensions and there won't be a ton of new diamonds minted unless they fly a LOT.
I am wondering if DL will use the next two years to look at the Diamond threshold and decide how to get rid of half the people who are currently diamond. That was their stated goal when they raised the MQD's to 35k and I doubt that has changed. So, I am contrarian here I guess. I see the MQD threshold holding steady for two-three years while these status extension work their way out. I would guess that about three years from now everyone will have more or less burned the extensions and DL will know what their pool of diamonds will be. I bet we see an adjustment to the MQD level at that time to target a number of diamonds. The howling here will be record breaking because by design half of the diamonds will be gone.
I am sitting at 12.5k MQD right now. I have another 8.5k booked through june and should be able to hit the 28k with little effort. I also am sitting at 3k PQD on UA with another 12k booked there. I think I should be able to maintain diamond/1k without much effort (I will have to fly a bunch of segments on UA which SUCKS....). I will probably do RDM as a result since of the three that has the most value. The number of extensions here tells me that the next three years will be unpleasant on DL due to the continued bloated elite ranks. I see zero value in a status extension at this time since basically I get four GUC's with questionable value and the ability to be number 1-6 on the upgrade list.