Originally Posted by MidnightDraven
In theory, imeddiately (/however long it takes for O2 to activate everything).
If the PIN of the BB is still registered with a BIS account, it cannot be registered for a BIS account on O2 = no data.
I thought the de-registering of the PIN from another SIM/carrier was automatic now, upon detection of a new SIM in the BB?. This is what I gather from Google...