Note: The connectivity was hotfixed by temporarily adding HE as
CZ.NIC provider in ASPA, and later returned to normal (checked right
now).
It makes me very sad to hear that the solution to this involved informing in ASPA HE as a provider.
My greatest hope regarding ASPA is (or was) that any of the ASNs exhibiting this behavior—taking peering routes and advertising them to downstream customers as if they were part of their own customer cone—would be publicly vilified.
--
Douglas Fernando Fischer
Engº de Controle e Automação