I ask this because a friend who maintains a relatively small (20 - 30) list of members of a walking group has found that notices of recent events sent to subscribing members of his group were not received. Other, non BTInternet recipients did receive the notices. My friend's ISP is PCXinternet, not BT, but there seems to be a pattern of BTinternet users not receiving the emails. My friend asked several members of his list and they said they had not received the email and the common element seemed to be that they were BTInternet users.
I also have a larger (c. 200) list of people to whome I send periodic notices of events. I have weak evidence of a lack of response to a recent distribution email from BTInternet users. This may be simply the recipients choosing to not respond, but ... The question is in the air.
Has anyone else seen anything similar?