Since this message, which showed up yesterday, actually took 6 days to post on the DML (sent on May 4), I'm not sure if a suggested 24-hour wait makes sense. There appear to be different issues that have caused posts to be blocked completely (usually spam filter issues at the DML end) or to be delayed for days (probably gmail issues).
The good news is that the Cleveland Museum of Natural History archive is back up and working for the month of May at:
I have been contacted by a number of people who check the DML archive for new papers and news, and were concerned.
As noted earlier, the DML has another archive and a live-feed at:
For now, I think I will still try to resend blocked posts after 20 minutes or more when they happen. Apologies for multiple repostings that sometimes happen. There are many cases in the which the original posts never shows up, so it's hard to predict is a post has been blocked or only delayed. I can hope that the information is what counts and reposts because of technical problems are an occasional annoyance that people will excuse.