Ba j zag-tpa-arn €1583
 

I've been keeping an eye on open-jaw biz fares, traveling from just about any place in the Balkans to TPA in early August and back to ARN around Xmas. The fare on BA had been running in the €1850-2050 range from ZAG for the dates I was checking. That's a good fare, and I was ready to book it yesterday. I was pleasantly surprised when the fare dropped to €1583 ($1741). It looks like it works from ZAG for a lot of dates in early August (maybe more, didn't check) with an overnight in London (arriving at LHR from ZAG and departing to TPA the next day) and departing from TPA on December 24 or 25 (TPA-MIA/ORD/PHL-LHR-ARN).

Here's an example:

Aug 12: ZAG-LHR BA0849
Aug 13: LGW-TPA BA2167
Dec 24: TPA-MIA BA4436 (operated by AA)
Dec 24: MIA-LHR BA0206
Dec 25: LHR-ARN BA0778

For an AS MVPG75K, this itinerary will earn 41,566 Mileage Plan miles (approximately 4.2 cents/mile) with the 125% MVP75K bonus and 150%/250% class of service bonuses on I/J fares:

ZAG-LHR (J) 852 miles + 1065 MVPG75K bonus + 2130 CoS bonus = 4047
LGW-TPA (I) 4427 miles + 5533 MVPG75K bonus + 6640 CoS bonus = 16600
TPA-MIA 0 miles on AS
MIA-LHR (I) 4425 miles + 5531 MVPG75K bonus + 6637 CoS bonus = 16593
LHR-ARN (J) 911 miles + 1138 MVPG75K bonus + 2277 CoS bonus = 4326

Class of service bonus on BA
 

looking at your mileage calculations. I am under the impression that "I" class fares only earn 50% COS bonus. It looks like you are using 150%. Am I looking at things wrong?

R and I fares earn a 50% CoS bonus plus a 100% additional bonus. The latter is only RDM, but it's still a nice bonus. Also, every Club Europe segment I have ever purchased as part of a BA TATL Club World ticket has coded as a J fare. An MVPG75K earns 475% of miles flown on those. Here's an example:

01/xx/2017
BRITISH AIRWAYS Flight 758
LHR BGO
Credited
Miles 648
Bonus 2,430
Total 3,078

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