Updated_at field not updating with timesheet changes

Posted on behalf of customer. Original posting date 2014-08-12.

I've been working with timesheet entries via the API.

When a timesheet entry changes state to Needs Update, Ready, or Locked (waiting, accepted, submitted in the API), I can't see that the updated_at field changes. I also don't see any record in the changes API call.

Am I missing something? Is there some way for me other than above to find when a timesheet entry changes state? I'd like to poll for these changes but I can't seem to determine any way to reliably poll for a change to state.