Thanks for the quick response. I did initially look at fullEnvelope but it wasn't changing, so I assumed it wasn't honoring the definition expression. However, that was because I was logging before the layer had refreshed. So, fullEnvelope will work, but that leads to another question.
Is there an appropriate notification that indicates all layers have been refreshed or would I need to monitor each layers AGSFeatureLayerDidLoadFeaturesNotification?
Thanks again!
Matt