United only flies to two of those six cities (DXB and TLV). How are you supposed to change to AMM/AUH/BEY/EBL with the restriction of "your new flight must be a Untied flight...". I swear nobody proofs any of these "important notices" coming out.
I'm _guessing_ they'll let you switch to those cities if flights are operating and you'll have to take LH/OS/LX/*A and connect to/from a UA long haul. But that's not what the wording says at least.
-RM