Hi rtsbz,
My apologies for the delayed response. Let me help you rectify the issue with regard to the refresh interval for subscribed calendar.
We will need additional information from you so that we can identify the root cause of the issue. Please refer to the post of my colleague, Roniel_D., and provide the answers to his questions on your next reply. You can provide the affected Microsoft account,
the Calendar name, and the link of the subscribed calendar in the Private Message tab that I have opened for you. You need to sign in to this website and click
Private Messages across All Replies to see the tab.
We will be waiting for your reply.
Thank you.