So, what's happening here is, the list of sites to choose is a preference rather than part of the search. When you open the sites list and save your changes, those settings will be used for all future searches until you change it again. Except... if you saved an alert with a different set of sites than the one you're now using, and you pull up the results from that search, we will show all the sites that were saved to the alert, because otherwise you might not see the cars you were alerted on.

However, we didn't want to just override your setting, since that might not be expected. As you've pointed out though, that causes a different kind of unexpected behavior, in that next search (including if you refresh), it then reverts back to your saved site list. We will need to address that.

We'll dig into the best way to do that, but for now I wanted to explain exactly what's going on, so you can hopefully work around it in the meantime, while we iron this out.