I've did some testing on my end and unfortunately, it doesn't seems to have a way to re-order both the Calendar as well as the Event as of now..
Playing around with adding new calendars I notice that the Calendar seems to be arranged in reversed alphabetical order.
I've also found the 2 suggestions that is currently under Gathering Interest status that maybe worth to give them a vote:
Hey there, folks! For most of us, the past six months- yes, you read that right- have been a journey. More people than ever before have pivoted to working remotely, and navigating being on-scre...
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