Champion Permanent new player missions are completely gone?

So I wanted to get a few one trick accounts for certain champions, and made new accounts. Some of them have the new player missions (or had, since most / all are completed now), the ones where you get the Ahri/MF/Lux/Yi/Darius champion permanents... some of them don't have these missions.

Is it dependent on the account's creation date or is this a bug? I don't recall seeing anything about those missions disappearing on any of my OTP accounts. But for like two of them it's just gone completely.

(Also yes, this is my EUW account for KogMaw, but the accounts missing the missions are NA.)