You can reopen batches that were recently saved in a Space. They are available from the Batch screen's Recent Batches section.
Steps (Web App)
To reopen a saved batch:
Log in at app.photoroom.com.
Select the Space you want to work in.
Select Batch.
In the Recent batches section, click on the batch you want to reopen.
Photoroom opens the batch in the Batch editor.