I have a workflow that pauses for one or five days based on whether the added list item is "emergency" or "normal" priority. I’m changing the workflow so that it will pause until a specified (calculated) date. If I already have workflows out there that were run (and presumably paused) for one (or five) days, when I update the workflow in production to “pause until XXX date”, will the old workflows that had “pause for 1 (or 5) days” resume when the one or five days is up? I'm assuming the customer can live with the old list items having the one or five days and the new ones having the specific date; I just want to make sure SharePoint will resume the "old" workflows.
Any workflows in progress will follow their pattern, so yes those in progress would remain paused for 1 or 5 days. Any new items created after the update will follow the new workflow rules. Eventually, they'll all work themselves through and everything will operate under the new workflow.