Let's Encrypt is sending this notification.
Older devices (iPhones before 5, Android before v.7 and other devices will be affected).
Just to keep an eye on it.

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Hello from the staff at Let's Encrypt.

On September 30, there will be a change in how older browsers and devices trust Let's Encrypt certificates, resulting in a minor decrease in compatibility. If you run a typical website, you won't notice a difference. Devices and browsers running up-to-date software will continue working fine, and we've taken steps to make sure the vast majority of older devices will too. If you run a large website, or need to support less common software (particularly non-browser software), you'll want to read about the details at:

https://letsencrypt.org/docs/dst-root-c … mber-2021/

In either case, no action is required from you. We're letting you know so you can provide answers to any questions your site visitors may have.

Here is a sample hostname from one of your current Let's Encrypt
certificates:  mail2.rameservice.com

Since 2015 we've served the world with 1.6 billion free certificates, each one providing security and privacy to people on the Web. It's work that's 100% funded by charitable donations since we are a nonprofit. If your company is interested in sponsorship, please email sponsor@letsencrypt.org. If you can make a donation, we ask that you consider supporting our work today: https://letsencrypt.org/donate/ Thank you.

- The Let's Encrypt team

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