please check screenshots, but basically when i load the page where my calendar block is on - this is how it looks on load
i need to then toggle between month/week before the calendar then properly displays as shows below:
I’ve noticed this issue as well, which is why none of my calendar blocks are live to users. Once there’s a fix/update, hoping we can make better use of this 
Thanks for reporting this we will get this addressed soon.
@danyalamriben and @flavi can you pls DM me some details so we can check this on your apps directly ?