Exchange services still available during the 30-day grace period after subscription expiration?

I've gone through multiple articles, but it's still unclear to me what the limitations are on service access during this period. I'm currently working on a migration which uses a tool that relies on EWS and necessitates an active mailbox license.

I would like to know on whether mailboxes will remain licensed and if EWS access will remain active/enabled during the 30-day grace period?

According to the Microsoft article below, all data is accessible to everyone, and users have regular access to O365, files, and Microsoft 365 apps.

https://learn.microsoft.com/en-us/microsoft-365/commerce/subscriptions/what-if-my-subscription-expires?view=o365-worldwide

This other article (not from Microsoft) states that MAC Outlook, which utilizes EWS, is not included in the 30-day grace period.

https://www.computerworld.com/article/3672968/what-happens-when-an-office-365-subscription-expires.html

Best regards,