Well supposedly t-mobile was doing the same according to rumors, but t-mobile finally added some info saying they were not. Then added that some phone may not work because of old software and the usability to upgrade. Though they didn't specify what SW needed updating.

But in the end of the day it's Feb and my n900 still works!!! Thank the lords, since the my PinePhone is not yet ready for my daily use.

So maybe it will be similar in your case, but you still have 2 years of n900 fun.

x