What are my best options with IOS 5.0.1?

[jadog]

I would like to jailbreak my phone (untethered if possible), but also preserve the baseband so I can use it with a T-mobile sim card. I just bought the phone from someone who was previously using it with AT&T. It has never been jailbroke and the current firmware is 5.0.1 and the baseband is currently 05.16.05.

From what I understand, I have to be on IOS 4.3.3 or earlier to be untethered. But can I downgrade safely without a previous firmware backup? Or would my best option be to just sit tight and wait for an untethered release to arrive that will also preserve the baseband so it can be unlocked?

Thanks for the expert advice!

 

[Jmills87]

If your phone has never been jailbroken before how could you possibly be on 5.0.1 with a 05.16.05 baseband? The 5.0.1 baseband is 04.11.08 which is not unlockable. No way to downgrade to 4.3.3 without your SHSH blobs.

 

[jadog]

I just double checked again and the baseband is correct - 05.16.05, but what you are saying is that it must have been jailbroken at some time? So that means that it can still be unlocked after a jailbreak? And the only method for doing this at the time since I'm on 5.0.1 is tethered, correct?

 

[Jmills87]

If you're on iOS5 and your baseband is at 05.16.05 that means that whoever updated your phone to iOS5 used sn0wbreeze custom firmware to do so, otherwise you would not have that baseband. The only way you can unlock 05.16.05 is to buy a Gevey Ultra SIM.

And yes, there is only a tethered jailbreak for 5.0.1 right now.

 

[jadog]

Thanks, that's very helpful. Is there any reason why I shouldn't try the tethered version? I can always go to the untethered when it's released, or is that a big process? I checked out the Gevey Ultra SIM card and was wondering i the card needs to remain in the iPhone? I also checked and they didn't have my baseband in the list of ones that are compatible.

 

[Jmills87]

Ok ya, I just realized 05.16.05 is the 3Gs baseband lol. So what you'll have to do is update to the iPad baseband(06.15.00) if you want to unlock and then use Ultrasn0w and the Ultrasn0w 5.0.1 fix.

 

[jadog]

Cool. So I don't have to purchase a special SIM card? So I need to do it the following order, correct?

1.) Jailbreak using the latest version of redsn0w (.9.x) or sn0wbreeze (2.x)
2.) Install ultrasn0w and then the ultrasn0w fix for 5.0.1 to upgrade the baseband to 06.15.00 (Can I do this in Cydia or is there someplace else I need to download from?)

I understand that if an untethered version comes out, then I have to untether my device (using iBooty or similar). I hear it is rather complicated, so would the recommendation be to wait for the untethered version to be released or will it likely by quite some time?