You should have received an email as soon as there was a licensing issue as mentioned in the below kbase article.
" When out of compliance, due to expiration of licenses or insufficient device counts, you will be notified by e-mail. "
https://documentation.meraki.com/zGeneral_Administration/Licensing/Out-of-Licensing_Compliance_Warni...
I know these are working because I received an email for an insight Trial I had on one of my networks.
Meraki CMNO, Ruckus WISE, Sonicwall CSSA, Allied Telesis CASE & CAI