Moving 3 unlocked 3G phones FROM T-Mobile back to ATT

[stevehookem]

I have three unlocked 3G phones currently being used on T-Mobile. I really HATE T-mobile. I'm thinking about going back to ATT.

What's the best way to go back (and least expensive) and retain my Jailbreak? I would like to upgrade all three to OS 4 too if possible even if I don't go back.

All three are not factory unlocked. I used Blackrain for two and the DevTeam's stuff for the other.

I'm completely confused with all the different methods out there now. Help!

[heyyyitsjordan]

if the phones are already unlocked, then just insert the at&t sim cards... all you need to then is change the cellular data settings to get ur 3g and mms working...

if you want to upgrade to iOS 4.1 (wayyy better than 4.0, 4.0.1, 4.0.2), then it depends on what baseband, bootrom, and iOS version the phones are currently running.

[stevehookem]

Do I have to sign up for an iphone "plan" there to get web and messaging?

My 3G: OS 3.1.2, 04.26.08. How do I get the rest?

[heyyyitsjordan]

i would imagine so, but im not entirely sure. i know with tmobile, you could use various plans to get the same features (i was able to access web on the iphone with an android plan, then i switched to a "smartphone" plan and its still the same). so theoretically, it should be the same with at&t... but im not 100% positive.

How to Check iPhone 3GS New Bootrom / Old Bootrom (iBoot) Version | Redmond Pie to check bootrom version

[stevehookem]

Baseband: 04.26.08
Bootloader: 6.4
Model: MB704

[TBSS]

If your going back to AT&T why don't you sell your 3G phones and sign new 2 year contracts and get new iPhone 4's. You won't be able to jailbreak until the new jailbreak is released but you will have better phones for very little money spent.

[stevehookem]

If I get the new iPhone 4 that is not jailbroken yet, can I put all my apps that I have on my current 3G phone on it when I hook up to iTunes? Many came from places other than the app store....

Still confused some, sorry.

How best to move to ATT. I need 3 lines. I currently have 3-3g phones. When I sign up, I'm getting 1-iPhone 4 and two additional lines. I want to use two of my current 3g phones on the other two lines.

Do I get the iPhone 4 with the data plan and unlimited family text and also two free phones with no data added? Put the sim cards in the iPhones when the free phones arrive? Will I get data on the 3g phones this way?

What's the best way to switch back?