Does the Feb 26th deadline apply only to NEMstakes that are on the NXT asset exchange?
2/26 is also the deadline for Phase 2 redemption for BTT users.
Is NEM already launched?
no not yet. redemption for AE stakes will be coming to a close first (on the 26th, stakes become worthless after that date.) and then launch will come after that. not sure how long after though.
And BTT stakes， Is it become worthless eithe after the date?
No, the BTT stakes will have 2 months in the extended redemption period, which will be announced later.
I'm confused. question:
1. "the Feb 26th,the deadline"，is there anybody tell us more authority and right;
2.before the deadline ,what must we do?
1. Makoto is a core dev. How much authority do you need ? (and since you don't seem to know a lot about the project, how would you know who has authority?)
2. You should have followed
https://forum.nemcoin.com/nem-news-alerts/updated-redemption-guide/My guess is you missed phase 1. If that's the case then there is nothing you can do other than wait for instructions regarding the extended redemption period after launch.