Veteran rewards....

[Niwashi]

Self-contradictions are silly.

Exactly.

have the sort of shop be more like "Oh, you've reached this many achievement points. Here, have any of these now-available certificates to trade in for the thing you want."

What it sounds like, to me, is we have to spend our achievement points to get the missing rewards we want.

players will be able to use their achievement points to purchase achievement certificates by speaking with Jonathas... Certificates can then be used to purchase rewards of your choosing.

You get certificates that you can then trade in for the things you want. And that's exactly the way you said you wanted it to work. Where's the confusion in that?