Originally Posted by maxheadway
I think the change by the airlines is more standard practice than luck. I'm just trying to figure out when it occurs and when it doesn't. I'm guessing when E+ seats are available, I'll receive the change, and when E+ seats are sold out, I'll get stuck in the back of the plane. But I'm trying to get a confirmation on that theory, or specifics on the upgrade policies. By learning the policies, I have become an informed traveller that can make better and faster decisions. Reading FlyerTalk comments makes me feel like have graduated from general membership to the next level.
There are two completely separated issues.
You are entitled to E+ seating no matter what your booking class (you are premier, right?). E+ is determined by elite status. Booking class plays no role at all there. If you are premier, you have E+ seating guaranteed as long as there's an open E+ seat in the plane. If you are not premier or higher, there's no E+ unless you pay for it or get lucky at the gate.
Y cabin of servicd refers to both E+ and E-.
The booking class is important in other situations, like priority for standby and upgrade and some booking classes give you a bonus EQM (in addition to the bonus you get as an elite, which is only RDM).
Coming back to booking classes, S is a booking class, Y is another booking class. Y is higher up the ladder. Both book into the Y cabin (E+ seating for elites, E- for anyone else). The Y booking class gives you a 50% EQM bonus and higher priority for standby, etc. So if for some random reason your booking class got changed to Y, then you got lucky in that sense.
Your boarding pass should contain both the service cabin (Y for sure) and the booking class (S or Y). That's the only way to know for youre. You should check your bp for booking class (again make sure you're not looking at service cabin).
Hope this helps

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