Hi,

I have some time-based workflows that are triggering when they shouldn't, and the problem appears to be that when I change the field on which a Time-Dependent Workflow Action is based, Salesforce does not re-evaluate WHEN to trigger those Actions.
Here are the details: we ship equipment and monitor whether the customer sets it up. As long as the customer has not set up the equipment, we send them reminders at various intervals after the delivery date. To do this we have a workflow rule with the criteria for sending a reminder (i.e. customer has not opted out of the program and has not yet set up the equipment) and then a number of Time-Dependent Workflow Actions to trigger the reminders.
We also can grant extensions to customers, which essentially moves their delivery date forward by the number of extension days given. (The Time-Dependent Workflow Actions are actually based on this field, which we call the Effective Delivery Date.)

This is where the problem comes in. Giving a customer an extension, thus changing the Effective Delivery Date on which the Time-Dependent Workflow Actions are based, doesn't seem to affect when the Time-Dependent Workflow Actions trigger. What DOES have an effect is changing the customer's account so that it no longer meets the initial criteria of the workflow rule. 
So it seems as though Salesforce is re-evaluating whether a customer meets the Rule Criteria, but it's not re-evaluating the times when the Time-Dependent Workflow Actions should trigger.

Any help would be much appreciated!