My offer was similar to other GS offers,
Milestone 1: spend $16,500 and earn 43,000 bonus award miles
Milestone 2: spend $18,500 total and earn 64,000 more award miles
Milestone 3: spend $25,000 total and earn 106,000 more award miles
But my son, who was Gold last year but GM this year, got:
Milestone 1: spend $1,500 and earn 18,000 bonus award miles
Milestone 2: spend $2,500 total and earn 27,000 more award miles
Milestone 3: spend $5,000 total and earn 45,000 more award miles
at $.019/mile, that comes out to a ~35% discount at the $5000 level. That's enough to make me cancel a few award tickets I got for him and rebook.