fuyao

Hi guys,
so this is kind of a tough one for me.
I'm AirBerlin Gold and I'm flying the following route (all in economy):
TXL-BEG op by JU
BEG-AUH op by JU
AUH-BKK op by EY

BKK-AUH op by EY
AUH-BEG op by EY
BEG-TXL op by JU

Every segment is marketed by JU.
Now JU is part of Etihad Guest and EY+AB are partners when it comes to status + lounge access etc.

But the information I can find online is not clear on a few things:

1) Can I do priority check in @TXL with JU and @BKK with EY?
2) Can I access any lounges in TXL/BEG/AUH?
3) Is +1 guest allowed at the lounges (loungebuddy says no)?

I read in the past that you can't enter the EY lounge as AZ Elite (I'm also that if it helps) if the EY flight is marketed by another carrier, it must be marketed and operated by EY so I'm afraid this will be the case for my itinerary as well.

Thanks!