Just as a point, you don't have to log off in your home city to get your bonus. Any city or town that you go into (barring a few) will mention your having gone into a sanctuary. Logging off there, you will get the bonus.

A reliable tell to see if you thought you were in a sanctuary and actually weren't, there will be a log-off timer that cues. That means you weren't in a sanctuary and won't get the bonus.