Hello @PeterC112 ,
Yes you can edit a table if you copy a previously built template or create from a saved reusable template with a table in it.
What you're wanting to do won't really be possible however, without a significant amount of manual work. You'd need to manually clear the contents from each cell in the top row, then manually move each subsequent cell up one by copying and pasting, then deleting the original cell's contents. Adding rows in the middle isn't currently available either.
If you're just wanting to have a calendar setup, I'd honestly recommend looking to a calendar-building program / site, or using a true spreadsheet program to build your events calendar, then insert that as an image or linked PDF. Another option would be to host the calendar on your website or social media pages, that your contacts can navigate to from links in your email.
For voting, suggestions, and voicing of use cases on adding more calendar-like enhancements to the table block, or a calendar-based block, I'd recommend checking out this Feedback thread.
See also:
Text links
Image links
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