DoneTonic offers you the possibility of splitting a PBI to redistribute tasks. This will allow you to create a new PBI from an existing one, you will only have to redistribute the tasks and define which ones will be executed in each of the PBIs, both in the original and in the new one:
Divide the PBI from the backlog
Just select the BIP you want to split and select the “Split BIP” option. In the split PBI you only have to choose a new title, a new description and drag the tasks from the split PBI to the new one.
Simple and fast.