Do we get "50% Discount on your next Exam" token for every exam passed?

Hi all,

As the title, do we get the 50% off token for every exam passed or just only once?
I have passed my SAA exam so I have a token now and I am planning to take SysOPS and SAP within this year. If 50% token is only given once, then I am going to save it for SAP. If we get it for every exam passed, then I can use it on SysOPS, pass the exam, get another 50%, then use it on SAP.

Thanks in advance!

-ystatit