Hey guys, second time I am using the forums, and thanks for the advice previously.

Ok my old iphone broke, sent it to be repaired and they sent me a shiny new one. I was gutted thinking it would have the latest O.S. but it was on 3.13 so I used the spirit JB and it worked fine.

Thing is like a lot of other people I keep losing my service, it will either display 'searching' or 'no service', and then regain the service.

Thing is I am working away all this week, and need my phone desperately for work. I have my works laptop on me, so was needing some help DESPERATELY.

Basically I want to remove the JB temporarily so I get full signal for work, and then JB again when I get home next week. Just need a quick fix, any advice would be greatly appreciated.

Thanks in advance guys.

Sorry just some additional info, I have tried 'reset network settings' loads of times. Also when I have been getting a connection phone calls do not seem to have been dropping.

From my (limited) understanding, you can remove the Spirit jailbreak by re-flashing to 3.1.3 -- this will re-lock and re-jail your phone. If you need to upgrade to 3.1.3 but maintain an unlock, and you already have an unlockable baseband, you can use the method detailed here to ensure you keep an unlockable baseband through the restore:

http://www.hackint0sh.org/f247/129972.htm

Good luck!