In a Nation Builder nation, I have a 700-member e-mail recipient list. The majority of these recipients were imported when my nation was set up a couple of months ago. Email to these recipients is solicited because they all pay a monthly/annual fee for membership.
I've sent about a dozen email blast in this time without problem, and I get stats on how many people opened links inside the emails, how many bounces, how many are ad addresses. However a couple of weeks ago, I sent one out and it first reported everything to be OK, with zero bounced, but after about 4 days, the bounced shot up to 117. This was highly irregular because the highest number of bounces before this was about 8. I had a look at the 117 and they are all Yahoo, AOL or Sky addresses, and since AOL and Sky go through Yahoo, we can assume that this is specifically a Yahoo problem. Here's the message that appears in Nation Builder next to each bounce...
4.0.0 Email was deferred due to the following reason(s): [IPs were throttled by recipient server]
I've done two more blasts since this, and the same thing happens. I've checked with a few owners of these email addresses and can confirm that the emails are not being received.
Is there anything I can do to help this situation, either on Nation Builder, on Google G-Suite, or on Yahoo? I've contacted Nation Builder support, but all they suggested was that I send a handful of emails at a time in order to rewarm Yahoo. But this could take a long time, especially since I have to wait 4 days just to see if it worked.
One thing that might be of interest, is that among the 117 bounced, two of them have this bounce message instead...
4.7.0 421 4.7.0 [TSS04] Messages from 188.8.131.52 temporarily deferred due to user complaints - 184.108.40.206; see https://help.yahoo.com/kb/postmaster/SLN3434.html
Any help would be appreciated. Thank you.