Agree with Lisa.

There is never any transfer of data between returns or years that happens automatically.  Proforma is a manual process.  Once the data from 2018 is transferred to create the 2019 return, what has been proforma'ed will remain static.  The only way to change the proforma data is to manually alter the prior year data in the 2019 return.  Don't think you can do another proforma/rollover without messing up your existing return.