1st step: ask a noc from present sponser
if he ready to provide you are lucky
2nd step: check your labor agreement
as per agreement you can move, but take care
it is difficulty. may your sponsor complaint against you.... it is caused ....
its almost true, but you can it may again depend on your relationship with the management
It is not mandatory to work 2years with your present sponsor if your present sponsor agreed than you can join any time with other company.