I didn't request anything, but just received the following challenge via email:
TrueBlue
UP FOR THE CHALLENGE?
We treat loyalty like royalty, and the Mosaic Challenge is a quick way to qualify for TrueBlue Mosaic in a short period of time. Just register for the Challenge here by September 7, 2015. You then have 90 days from your registration date to earn 3,750 base flight points. If you complete the Challenge in time, you'll qualify for Mosaic through 2016!*
As a Mosaic you'll enjoy great perks, on top of existing TrueBlue benefits, which include:
Be fee free!
JetBlue change and cancellation fees will be waived for Mosaic members and others on their itinerary.1
1st and 2nd bag free
You and others on your itinerary can check both the first and second bag for free - no matter which fare option you choose!2
Even MoreŽ Space
Stretch out and relax by redeeming your points for an Even More Space seat.
Even MoreŽ Speed
Cut down on the time it takes to get to your gate with complimentary access to an expedited security line.
Early boarding
Be among the first to board and get early access to overhead bin space.
Earn fast
Earn 15,000 bonus points immediately upon qualifying for 2016 Mosaic status.
Bonus points
Earn an additional 3 TrueBlue points per dollar on your JetBlue flight, for a total of at least 9 points per dollar if you book on jetblue.com.3
Dedicated Customer Service Line
Access to a dedicated Customer Service Line available 24/7.
Good luck!
I don't think it's a targeted offer, so if you have interest in doing the Mosaic Challenge, there's the offer!