@Tamar **********
Thank you Tamar. The reason I was confused was because I thought when one purchases a "return ticket" ...the outbound and return ticket shows both the dates on the one ticket. Therefore when you are checking in they can see at a glance that you will be staying more than the 30 days...But when you explained about the domestic flight episode, that explains it...
For myself, I think I'll just book a return flight within the 30 days and change it again after getting the extension....to save the possible hassle...I had a Retirement Ext. for 23 years and didn't have to care about this aspect of the flight.
Thanks again..Cheers.