I recently had a small issue, I noticed it because Automate stopped working, as did Hub triggered backups.
I noticed (after some trawling) that Defender had blocked the servers IP addresses (both IPv4 and IPv6). It seems that when Cron triggered a crawl (looked like a SmartCrawl or possibly a HUmmingbird cache crawl – I couldnt identify which but it was the act of crawling) that had 404’s, Defender blocked the servers own ip’s.
Given the way that the Hub works in most cases for these this meant that none of the automated updates/backups etc. worked.
I have since Whitelisted those IP’s and its fine. I Probably shouldnt need to though so thought I’d mention it here.
(I’m using WP-CLI to trigger cron by the way).
There is no need for any actual support as I’ve fixed it myself, but maybe something worth forwarding onto the Devs.