Original Rom for UK unbranded Omnia

[Guest kersey]

Hi all,

I need to return my Omnia to be repaired but think it would first be best if I flashed it back to it's original rom when bought the phone...trouble is I'm not sure what rom it would have been.

The phone was purchased from Phones4U and is unbranded and open to all networks. Have you guys any ideas what rom may have been on there or if not what would be a safe one to flash to as I don't want the insurance company blaming me for flashing the phone as a cause of the malfunction.

Thank in advance