Mitigate too many concurrent connections to Spectrum?

I sent a newsletter to my main list today and immediately had four messages bounce from Spectrum addresses (domains of and in this case but I believe there are others within Spectrum). After examining the bounce results (“sender rejected. Please see [Spectrum site] for more information. AUP#In-1310”), I found the following relevant info from Spectrum:

Spectrum limits the number of concurrent connections from a sender, as well as the total number of connections allowed. Limits vary based on the reputation of the IP address. Reduce your number of connections and try again later.

I’m using the AWS SES plugin. Is there any way to mitigate this, so that messages to Spectrum-owned domains could be spread out more to avoid these bounces? I’m guessing it’s not feasible, but I figured I’d ask.

Also, regarding the “try again later” comment, is there a way to do that without creating a new campaign, given that these recipients were already sent the original campaign? I’m not really inclined to do this, but if it’s easy and quick then I might try it.