Originally Posted by Rabaja

Yes, the LH/LX system has all the different numbers tied to the customer number. But that doesn't apply to partner airlines. For a few years I didn't even realize that LH gave me a different number when I got SEN. Using the original number worked just fine for mileage credit, both on LH/LX and UA (I credit UA flights to M&M). But UA never acknowledged by *A Gold status. I didn't notice or care until I kept on missing out on my first meal choice flying Polaris J SFO-EWR (transcontinental Polaris food is good enough to eat). After a polite inquiry I was told that as a non-status person I was at the back of the queue. I first suspected IT limitations, but eventually learned that using the new SEN number would register as *A Gold in UAs system. So, only through missing out on short ribs half a dozen times did I learn that LH/LX gives you a different number when reaching SEN and that you need to use this number to get *A Gold benefits on partner airlines. At UA this matters most for lounge access, which is complimentary for *A Gold but not for domestic J travelers unless they fly transcontinental Polaris from/to SFO/LAX.