The flurry of activity that you have seen is indicative of people checking out the property in order to assess the condition of it. The property is most likely scheduled for an auction of some type. It could be a trustee sale or it could be an auction for taxes. I checked the fidelity website for downtown auctions but did not see that address. It could still be scheduled but for something out of my range. It also could have recently gone back to the beneficiary and not yet be recorded. It could be scheduled for El Cajon as I did not check that queue yet.
It could be nothing either.
Don’t know what to tell you about who has moved in and who now occupies the home. There could have been a remodel at some time and that the home was reassessed as well bumping up the value.