Nimbostratus
MVPDid you try using a rate limiting rate class?
https://techdocs.f5.com/kb/en-us/products/big-ip-aam/manuals/product/aam-concepts-11-6-0/4.html
https://clouddocs.f5.com/api/irules/rateclass.html
You may also attach a traffic class under the VIP that matches the destination IP address is the one hosting autodiscover.xml
https://techdocs.f5.com/en-us/bigip-14-1-0/big-ip-local-traffic-management-basics-14-1-0/about-traffic-classes.html
NimbostratusI've looked into those, and it appears that rate limiting classes and traffic classes are applied from a VS context and affects the amount of traffic going through the entire VS. I am trying to get this narrowed down to a per user basis.
I'm still a little new to creating my own iRules, but there's got to be something that will let a session stay open until a table count threshold has been met.
MVPAbout rate class it should be applied only to packets matching the iRule if statement not every packet for the VIP will be affected.
Try looking into https://support.f5.com/csp/article/K14813 and "Understanding iRule mitigation" that has a SIP example that you may try to modify for your needs.