Not all recipients in BCC receiving my email message

@XfinityNicki​ Please let me know if you need more information. For example, do you need my email Subject so that you can find it on your server? Do you need sample email addresses which succeed and which fail? Let me know.

We may need to investigate this further, but first, we can continue some basic troubleshooting, if that's okay? If so, have you been able to ask the recipients of these emails, the ones who are not receiving the emails, if they have any blockers set up, or if they have any filters in place that could be blocking these emails from being received? 

I have asked a sampling of the people who are not receiving my messages to check their Junk and Spam folders. My emails are not going there. I've also checked that I can send individual emails to people who are not receiving my photography messages, so I know the recipient addresses are good, and they don't have some other email rule against my address.

I'm paying for Residential internet service. I understand that there is a limit of 100 emails sent per day. My email distribution list is only 58 names, so my emails should be able to be sent under the current limits of my existing service. I only send these 58-user emails about once every 2 weeks, so if there is a monthly limit, I don't think I'm hitting that either. 

Please provide the Subject line and Send Date of my email you found containing links to Google.com, Apps.photos, and Apple.com. I'm not aware of having sent any emails containing any of these links.

The best phone number to reach us would be 1-800-934-6489. 

Called that 800 number. Chat bot presented menu, no help. Finally reached the Xfinity billing department. But their job, according to the jovial Pierre, is to read me advertising about the free gifts available to me as a 40-year customer of Xfinity. So he forwarded me to the Technical Support department, where I was put on hold, and then they hung up on me. Redialing. Ok, now I've reached Customer Assurance Dept. John tells me that there is a "new rule" in which Comcast says we must limit distribution lists to 10 addresses, so to send to 50 recipients, I should break my dist list into 5 chunks, and send 5 different emails, each to 10 different recipients. Well. You can imagine how happy that makes me, how absolutely delighted I am with this stellar technology presented by such a soulless company.