Hello Maria, On Wed, Feb 04, 2026 at 10:23:39PM +0100, Maria Matejka wrote: ...

This is a known feature, mandated by RFC 9774, Section 3: ... It is still possible to `allow as sets` explicitly, if you really need to keep them.

Ah, so this is a case of the RFCs being ahead of what's actually deployed on the Internet. Sadly, I must accept them as otherwise there are holes in the routing table across a number of providers. If it was just 1 provider then new behaviour could be acceptable. Will have to revisit this in 2 or 3 years to see if ISPs have caught up with RFC 9774. Thank you for the quick response -- it is much appreciated. Cheers, -ben -- "Thought is the essence of where you are now."