Burke ticket 506916 mentions the following:

Delphi surveys can run an exec when returning from autosave, by setting up an <exec when="autosaveRestored"> anywhere in the survey. This block runs before showing the first question. You can use goto(target) within that block to go somewhere else other than the intended question. The question which was supposed to be shown is saved as p.autosaveStartedAt -- note that this can be None if the respondent has not started the survey already. Thus you can temporarily jump to another block, display some HTML code (e.g. "welcome back") and then jump back to the question that was intended to be displayed.

I think if exec block tag kb that mentions autosaveRestored could have this note about p.autosaveStartedAt added other research agencies could benefit from this knowledge.  

Michael