Premium Domain Support

After all transfer attempts with them have failed so far, now over 50 of my domains have been identified as premium domains. Does anyone know if there is a plan until when these so-called “premium domains” can be transferred?

Can you post a screenshot of that message referring to that premium status?

Sure, it on the same spot where they list unsupported tlds:

These domains are presumably flagged as “premium” by their registries. If you believe this to be an error I’d open a support ticket.

Thanks for your answer! Do you know how I can check if they are flagged as “premium” by their registries?

The respective registry should be able to tell you that, respectively the renewal price as well. If you pay the standard renewal price it likely is a non-premium domain, otherwise a premium one.