I have written before about the privacy email features of ProtonMail. (See https://duckduckgo.com/?q=site%3Aprivacyblog.com+proton+mail&t=h_&ia=web for a list of my past articles.) Now the company that produces ProtonMail has announced it will provide 99.95% uptime or better. 99.95% uptime means the service will be unavailable less than an average of 8 minutes per day.
The new service level agreement (SLA) ensures that if downtime in any calendar month exceeds 0.05%, the company will issue a partial refund to all customers.
The latest ProtonMail announcement may be found at: https://protonmail.com/blog/protonmail-reliability-sla/.