You can wear your bracelet even if you don't have internet connection, just make sure it does not run out of battery as this would cause data to be lost.
As long as you see the underside green sensor light illuminate when you start wearing it, and charge it completely every day, the Ava bracelet can hold up to 5 nights’ worth of data.
As soon as you have internet connection again and sync the bracelet to the Ava Fertility app, data held in the bracelet's memory capacity will be uploaded and displayed for you in the app.