After playing a bit with the new "!!" priority I ended up more than once with a red alert I wasn´t able to turn off.
I messed with the new priority on storage compactors and sweep orders and the normal red alert button.
(Mostly sweep orders for critical/vanishing resources like off-gasing resources or items a close critter could eat.)
=> There should be a way to downgrade all "!!" priority orders or highligh them.
(My bug report isn´t about not finding the tasks causing the red alert, but that´s could be problematic as well.)
Steps to Reproduce
Not 100% sure, but was able to achieve it just using "!!" sweep orders for resources a close critter could/did eat.
This issue has not been confirmed by a developer yet.