When I have a scheduled maintenance. I cannot see it in the uptime calender.
Possible it is sensible as future maitemance is not part of uptime stats.
But is there a way I can see maintenace in a calendar?
Abe here with Statuspage support. You are correct that a future maintenance is not included in the uptime calculation since it has not happened yet. The calculation is up to the current date.
As far as seeing maintenances in the Uptime Calendar view, it is not currently possible but there is an open Feature Request. I've gone ahead and added you to it. If it gets worked on, we'll do our best to let you know! I do apologize for the inconvenience.
Let me know if you have any other questions,