Will buying a phone off contract void my current contract?

[Blake Seaman]

I am on contract with my Lumia 920 and I qualify for an upgrade. When I took my brother earlier this year and upgraded him to the HTC One M8 (for Windows), the huge discount on the phone I received in the past was replaced by "Next".

My Lumia 920 is biting the dust a bit; I've really beat it up and the damage is actually causing it to be an unreliable device. I want to buy a budget windows phone off contract and stick my SIM card into it, and then upgrade to the next flagship whenever it does come out. I was told by the representative that doing this would void my contract and my eligibility for upgrade, but I didn't see any advantage to the upgrade anyway given we received no discount at all and were just put on a payment plan.

So my question is
1. Will buying a phone off contract and putting my sim card in it work?
2. Will doing so void my upgrade?
3. Is there a real disadvantage to this?

Thanks!

 

[Br1t]

1. It will work if you buy an AT&T compatible device with the same size sim.
2. No
3. None at all

If you are doing this and out of contract switch to a Next plan if you don't have unlimited data, it will save you money.