Did a new spam botnet come online recently?

For the last couple of days I see a sustained wave of attempted spam inbound. From a very wide variety of IP addresses, so it's not a single compromised VPS somewhere...

My mail server is very small, usually it rejects spam 40-60 messages per day, but yesterday it hit just over a thousand...

I'm using mtpolicyd to do Greylisting and Postfix filters out a lot of script-kiddie level non-compliant garbage as well. With additional layers of DKIM, DMARC, and some DNSBL's barely anything ever hits my mail box, thankfully...