Thanks for posting here in the Google Nest Community.
Good question. Let me give you more details. When your doorbell is connected to the USB charging cable, the status light will appear solid white when your doorbell is completely charged.
Check this helpful link.
Keep me posted.
Just checking in to make sure that you've seen our responses. Please let me know if you have other questions or concerns as I will be locking this in 24 hours if I won't hear back from you again. Feel free to start a new thread and we'll be happy to help.
I appreciate the help, Juni and JT.