Not using the VF router, I wasn't aware that it only displays the logs going back a day or so.
It's not completely uncommon that the displayed logs are shorter or less complete than those available if you download them to a file and then examine that. That said, it's still common with router logs that all you'll actually see are the MAC addresses and not any usable names (does vary from router to router).
If you are concerned though, I do believe the router offers MAC filtering with the ability to reject by default any MAC addresses that you've not set up as allowed. *Obviously if you set this up over a WiFi connection, you need to allow the connection you are using for the set-up BEFORE enabling the default reject. **The option is probably only available in the router EXPERT settings mode.
