No signal: what is saved and sent later
Runs often end where there is no signal. On the phone app, the two things you answer right after a run, the effort check-in (your answers about how it felt) and your run note, are saved on the phone if they cannot be sent, and sent by themselves when the signal is back (when you next open the app, or as soon as the connection returns). While they wait, the screen says Saved on your phone, will send when you have signal. Nothing is lost if you close the app.
If one is still not sent after about a day, the screen says it is not sent yet and that it is still saved. If the server turns one down, it says it could not be sent and asks you to answer again, so a note is never silently dropped.
What needs a connection. Everything else that changes something does: plan changes, moving a session, accepting the coach's cards and so on. Those are not saved for later, so you will be told rather than left thinking they went through. On the web app, nothing is held: the check-in and note need a connection to be saved.