Well i think it depends on operator ...

some can update the user's profile to access the 2G or 3G network by simply doing the same on the existing HLR.
This depends on the simcards. We have simcards that access both 2G/3G so all they need is a profile update.

Others require you to change your simcard if it does not support 3G.


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about the yu network and 3G ,, i dont think they are going to be ordering any 3G equipment soon... orange is more likely to second 3G before the other two.