Any instances of the process that are in progress will continue on the version that they were started with. Any new instances will use the new one. Once the last "in process" instance is completed that version is purged.
Thanks Paul, just to confirm you mean a new Application Version, not a new Process Revision.
I can see that if I update a process revision, then the existing process instances will start to use the new revision.
A new Application version seems to close out the old processes
Please confirm .. thanks
Yes that is correct.