We do not determine if a domain is a Premium domain or not, nor do we have a list of premium domains, ZACR Registry determines if a domain is a premium domain.
The reason why no ISP's are selling premium domains is that most billing systems can only sell a domain for 1 price and not have a regular price and a premium price and be able to adjust this on the fly based on what message we get back from the Registry.
After running into this issue early this morning with some premium registrations and your was one of the issues, then consulting with ZACR about it, we put in additional measures to now block any premium domain registration unless we perform it manually on our side. This was the only way to solve that issue. I can only assume that the reason for the delay was that our dev team were collaborating with the Registry in finding a solution and then to get a breakdown of premium domains that we could crosscheck against our records.