We had issues with a deployment from 28.7 to 29.4.1
Clients using radius eap-TLS were randomly unable to connect to network after upgrade to 29.4.1. We rolled back to 28.7 and clients were able to once again connect. We isolated 2 AP's and migrated them back to 29.4.1 and we were able to duplicate the issue. I disabled 802.11w and the client that kept failing was able to finally connect. I enabled 802.11w and the client was again unable to connect. I re-enabled it and client connected with no issues. We tried 2-3 laptops that were previously were unable to connect to an MR-53 running 29.4.1. Now they all can after the template change. We called Meraki support but we figured out the issue on our own.
Here is the change we made to the template on 802.11w