The API keys for third party apps still work if the developer (or Reddit) hasn’t revoked them.
I’m not sure about an API switch over, (migrating to a new version, revoking access etc), all I can remember is billing for API credentials starts rolling from 1 July and Reddit won’t start requesting payment for a month or so (citation needed)
Please correct me (with links to facts) if I’m wrong as I’m slightly out of the loop
Reddit left Reddit too little time to react to the changes. Probably. Unless they had planned this months ahead and just didn't communicate there's no way they had all up and running to latest spec in that timeframe.
Yeah I know, exactly what Christian argued. And Reddit killed his access early so he revoked the api key. Other developers are in talks with Reddit under an NDA it seems (making the apps subscription model)