Hello,
you can use the process persistence to persist the state of your session to database and then load the process session on another day. It depends how you want to pause the flow of your business process - persistence works only in safe points, you can use timer or your own service task for that. Or you may simply split your workflow into two business processes. The second process can be supplied with the variables which can be used from the previous business process.
Regards
Jiri Svitak