Send a Message not being received by @ntlworld emails

Hi,

So we have some members with @ntlworld email addresses that used to receive messages sent from LCR but from September 2020 just stopped receiving these. I've got them to check all the usual things; junk and spam folders, tested sending emails with others cc'd in, deleted and re-added emails into LCR - nothing seems to work.

I've requested access to their accounts directly so I can try to test more 1:1 but I really would like to know if this is a localised issue or is something more widely connected with @ntlworld emails.

Any comments or feedback welcome!

I'm guessing that ntlworld.com updated their DMARC policy to have stricter spam protection.

I'm suspecting the best way to fix this is to have ntlworld's customers contact them asking why they're not getting mail from noreply@churchofjesuschrist.org. I say that because ntlworld has a interest in serving their customers, but may be not interested in working with outside groups trying to email their customers.