quick question, any issues with flashing before I Port over my perm. phone #

[jtpindc]

I got the HTC mogul and still have the temporary phone # sprint assigned to it but eventually will port over my phone # from another carrier.

will there be any issues if I flash this phone to a custom rom before porting over my permanent phone #? (e.g. from sprint, etc.)

I'm a newbie to flashing so just don't want to brick it and not being able to make/receive calls if I port over my perm. # first

thanks in advance