Heads up Esme, I noticed that Cronofy for Trello kicked me off and then when I tried re-authorising, produced loads of joined cards in my Personal list on my old board My Stuff.
I did the only thing I could, even though it was a bit drastic.
Closed and deleted old board - I'm an Admin -, created a new board, decided to close my account with Cronofy and also cancel the subscription.
I'm sticking to using Planyway to sync solely with Google.
That now seems to be working.
I recommend using the following settings:- All Cards, Default colour for card labels, and Free.
I hope this helps everyone here
Planyway is proving to be absolutely solid.
By keeping the sync settings as I described, (All Cards, Event Colour - Default, Show Completed - No, Show as - Free) the sync works perfectly.
Also on Windows Calendar, as I have two day views, just having Planyway syncing to Google is perfect.
Less clutter.
Overall, I recommend it, especially as Google seem to have improved the ping rate on syncing.
Awesome! Thanks @Charles Stewart