@SadieSays @thomasfuchs I initially thought it was the case, but I have checked - my instance is never blocked when I notice clearly missing replies (And I don't know why someone would block me unless they are just actively blocking everyone they think is banal). Nor do I block any instance myself. It feels more like something doesn't know to relay the reply to me (or forwards it slow enough that the conversation is no longer relevant by the time I get it).