The promotion runs for several weeks, another week or two won't matter in the big picture... PLUS, think of the HUGE increase in customer relations. Going the extra mile has a tendency to pay off in the long run.
so how far back do you go? 1 day, 1 week, 1 month? there will always be somebody who will get hit by the cutoff... so that person will complain why they missed the cutoff since they bought it 2 weeks and 1 day ago...
honestly it's sad to see so many people feel entitled... this is the problem with america... we can't be happy with what we have, we always have to worry that somebody else got a better deal...
you bought a nice gun... with lifetime warranty... you can shoot it till it breaks and they will fix it... 75 dollars of mags is 5 boxes of ammo at best... you will spend that much in one range trip shooting your excellent gun...
get to the range and break those springs in... and every shot you take remind yourself why you bought an xd/m..