Hello, 

[INSERT PRACTICE NAME] doctors and staff hope you and your loved ones are doing well. We apologize for any sudden changes to our schedule or hours that may have impacted you. We're working to resolve the issue so we can get back to our regular schedule soon. In the meantime, please visit [INSERT PRACTICE WEBSITE/SOCIAL MEDIA ACCOUNTS/ETC] for our updated hours. If you have any questions, please feel free to call, text, or leave a voice message at [INSERT PHONE NUMBER] if you have any questions.

We acknowledge and appreciate your support and flexibility and look forward to seeing you soon!

Sincerely,
[INSERT PRACTICE NAME]