Testing now that rule is enabled...

MAIL FROM: 250 2.1.0 Sender OK
RCPT TO: 250 2.1.5 Recipient OK
DATA: 354 Start mail input; end with <CRLF>.<CRLF>
Result: 250 2.6.0 <c3e4d1a5-7e36-4453-96b6-5b5fd2da8123@CH3PEPF00000017.namprd21.prod.outlook.com> [InternalId=63479616642758, Hostname=SA6PR02MB10432.namprd02.prod.outlook.com] 9255 bytes in 0.171, 52.709 KB/sec Queued mail for delivery

Still accepted - may need another minute to propagate.