OK, just wanted to close-loop on my actual experience:
1) My connection time 2hr 35mn from T3 to T5 was indeed enough. It was very efficient.
2) Wasn't allowed to use FastTrack security line; they checked my BP (only BA world trav). However, my line moved much faster, so there.
3) AA in MIA issued both boarding passes, priority-tagged my luggage (which was the 2nd bag to appear in Dubai). No problems.
4) In LHR, I was unable to upgrade BA world trav+
The upgrade couldn't be done at the customer service kiosk manned by two agents in T5 or at the departure gate (I'm such a newbie!). They directed me to the Customer Service office at the other end of the terminal; I didn't want to risk the gate closing without me.
On the return from DXB-LHR, I was able to upgrade for $210. It was a 2:00 AM flight; I had an empty row to myself. Worth it.
5) I brought only the 20" wheeled carryon and an expandable messenger bag/purse; when I wanted to carryon both on some flights, I was able to.
HOWEVER, I did encounter some stiff resistance at Dubai DXB's BA priority check-in counter about "two carryons flying to the USA".
I had to show my oneworld Emerald/AA EXP card + printout of AA's travel policy re: carryon exemptions for elites to take both bags with me.
6) In T5, I didn't partake of the lounges (due to err, time and shopping...). On the return, I had a very good experience at T3's Admirals Club (shower, food, drinks).
All in all, an excellent transit experience in LHR.
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I have AA EXP/oneworld Emerald status.
I will fly ticketed AA roundtrip MIA-DXB via LHR.
Have not connected at LHR in a while, hence my posting.
The AA legs (MIA-LHR) + (LHR-MIA) are upgraded using eVIPs.
The codeshare BA legs (LHR-DXB) + (DXB-LHR) are economy -world traveller class.
Questions:
1) Outbound, I have 2hr 35mn connection time - is this enough?
LHR website currently shows 120 mins, yet it's now down to 90 mins.
*Transfer drill: Deplane at T3, follow purple FLIGHT CONNECTIONS signs to the shuttle for T5, take the lift, walk purposefully, don't make eye contact w/ carryon dragons, undergo security*
2) As oneworld Emerald, may I still use FastTrack security line at T5, even though I'm ticketed BA world traveller/econ to DXB?
3) AA at MIA will issue both boarding passes.
Will I need a BA boarding pass for the DXB flight to replace the AA-issued one?
4) Is there a way to upgrade the BA legs upon arrival at LHR?
I checked on this via AA EXP agent; net-net, AA re-tickets at cost of full J class tix. Too rich for me.
5) Luggage: 21" wheeled carryon + 17" wheeled rolling tote.
I'm very petite, and the 21"carryon always looks huge next to me; twice (MAD and MIA), I was made to check it even though it is w/in regulations.
So the 21" will be checked through to DXB.
Will carryon only 17" + camera bag.
6) LHR T5 lounge access:
Do oneworld Emerald still get access to T5 lounges (GalleriesFirst, GalleriesClubSouth)? It seems YMMV?
I printed the oneworld Lounge Access page to bring with me, just in case.
But what really happens at T5?
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