Latest Update (6.6.1 to 6.7) breaks my site.

I’ve rolled back my website now but when I updated to 6.7 I had a message saying something along the lines of “This website is currently unavailable due to scheduled maintence. Check back in a few minutes”.

I left this for about 30 minutes before rolling to a backup of my site to fix it. I then tried again and had the same problem. My site is https://www.ultimatep.com. Are there any known reasons why Jetpack causes this?

Thanks

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