According to adduplex Microsoft might launch several range of devices at MWC 2015. From mid-range to high ended smartphones. Notice these are unconfirmed information by Microsoft:
RM-1031 looks like an android phone, Nokia XL.
RM-1062,63 along with its variants of 64,65,66,67 seem to have a 720×1280 screen at 5.7 inches which can be a probable announcement at the MWC
Why Microsoft Nokia instead of Microsoft Lumia???
Microsoft will hold a press conference at MWC 2015 in March 2 at 8:30 a.m CET