How do 'auto update' sites know what version they have?

FlightAware ADS-B Flight Tracking
1

Currently, the my website statistics say I have version 2.0. I use the autoupdate feature.

How do I know if I have 2.0.3 or 2.0.4 …???

Thanks.

2

I picked the " upgrade and restart PiAware " option and sent the command. After that my stats page was updated to say : Feeder Type: PiAware (SD Card) 2.0-4

YMMV

3

You can run “piaware -v” or “dpkg -l piaware” to see what you have installed.
The data backing the website’s idea of your version is updated when you connect, and the exact version wasn’t recorded until recently (only the base version), so if you have a long-lived connection the website display might not update to show the exact version until you reconnect.