Upgrading Firmware to 4.2.1 W/ out Affecting JB or BB?

[dylanmoro]

I jailbroke my Iphone 3gs on 4.0.1 and want to get 4.2.1 and I know there's a JB for it, but how to I only upgrade to 4.2.1 and not all the way to 4.3?

I chose "make my life easier" on Cydia, so I have the SHSH blobs.

But do I just download the firmware from somewhere and restore it to 4.2.1 somehow?

 

[Applejuiced]

Follow this.
http://www.iclarified.com/entry/index.php?enid=13931
You will need a mac.
You will have to create a custom JB 4.2.1 IPSW that doesnt update the BB.
And you'll also need to use Tinyumbrella to restore to that 4.2.1 JB firmware.
Make sure you dont restore to official 4.2.1, that will update your baseband and you will lose your unlock.
Be extra carefull, double check everything and make sure you understand everything before you attempt it cause you might not be able to use your iphone on unofficial carrier if you mess up.

 

[dylanmoro]

Follow this.
http://www.iclarified.com/entry/index.php?enid=13931
You will need a mac.
You will have to create a custom JB 4.2.1 IPSW that doesnt update the BB.
And you'll also need to use Tinyumbrella to restore to that 4.2.1 JB firmware.
Make sure you dont restore to official 4.2.1, that will update your baseband and you will lose your unlock.
Be extra carefull, double check everything and make sure you understand everything before you attempt it cause you might not be able to use your iphone on unofficial carrier if you mess up.

Thanks man.
Alright, the link you sent doesn't mention tinyumbrella, do I need to use it?
Plus I'm using at&t still so an unlock isn't vital, I just wanna keep my BB low in case i wanna switch carriers in the future. I just wanna make sure I keep all my apps from Cydia and Installous.

 

[Applejuiced]

Thanks man.
Alright, the link you sent doesn't mention tinyumbrella, do I need to use it?
Plus I'm using at&t still so an unlock isn't vital, I just wanna keep my BB low in case i wanna switch carriers in the future. I just wanna make sure I keep all my apps from Cydia and Installous.

You should just run TU first so it saves your 4.2.1 shsh blobs and so on. Then close it and use pwnage to do the rest from the tutorial.
You can only maintain your BB with pwnage tool so use that.
This way you can have the option to unlock in the future or sell it unlocked.
You shouldnt have a prob.