Single-bit errors in DRAM are caused by the capacitor that stores the data being discharged. This means that the transitions happen in one direction: from charged to discharged. With parity RAM, you can tell that an error has occurred, but you can't tell what the error is. The parity and ECC checks happen in the the digital circuitry and so have no knowledge of the analogue state. Since ECC uses Hamming codes, it can detect more than single-bit errors, but it can only fix one bit flip (the bias isn't actually required, but it does make the code shorter).
In the good ol' US of A if you bring your phone to another company, you pay the same thing everyone else is paying. No discount for not getting a new shiney through the new company.
If you bring your phone to another company, you are not going to get a contract with a phone, you're going to get a SIM-only plan.
"Spock, did you see the looks on their faces?" "Yes, Captain, a sort of vacant contentment."