TidyCal

Overall I think this is a good product for the cost and has some great customer service representatives.

However, I don't have or wish to use Google Calendar, Apple iCal, and Microsoft 365 Calendar, so was hoping that there may be on option to integrate with other emails clients such as Thunderbird or Protonmail.

As such, I will be looking for a refund, but if in future wider integration is possible, I would definitely consider buying this product again.