Default [Q] get "updated" android ver' on same kernal?

some years ago I owned a motorola milestone.
on the Milestone the last official update was 2.2 (froyo), but the dev meneged to create a newer ver of android for this phone
even the BL was locked.

I own now a chines MTK phone - have 4.2 JB, there is a chance to create a newer verision of android to this phone?

(BTW sorry for my bad English)