Originally Posted by
SkyTeam777
Would Turkish be able to tell if you had credited the miles elsewhere? Judging from the consumer-facing IT, systems are not often connected despite alliance claims of seamless service.
Yes. When you submit a mileage request the FFP contacts the operating airline for payment, the operating airline should then identify they have already credited miles elsewhere and decline payment, which then results in the FFP decline the mileage request.
Nowadays this check is supposed to be fairly instant across *A airlines & their FFPs.