The correct answer is #3. On a restricted ticket, the return must occur no later than 30 days after the outbound. If you do change the return flight (but still occurring within 30 days of the outbound), a $75 change fee plus any difference in fare class, if applicable, will be charged (unless you are lucky and you get by without paying these fees, which does happen). The routing, however, must remain the same. You cannot change the routing on a restricted ticket.
An exception to this rule would be an e-saver fare, where the return is limited to the exact days offered in the specific e-saver offered.
[This message has been edited by Sheryl (edited 03-27-2000).]