The ASDS thread is getting a bit cluttered (including by me) due to discussions of the ASDS support ships unrelated to ASDS, so I thought I'd try starting a new thread.
Examples would be Go Quest, NRC Quest, Rhea, and Elsbeth III, when they are conducting activities unrelated to ASDS (such as the search for CRX-7).
The two Quests have been seen conducting what appear to be sonar search patterns off Florida and California. In the case of Go Quest off Florida, this seems to be part of the search for CRX-7 debris (whether from Dragon or the LV).
But what is the activity off California? Wild speculation: a test to fine tune sonar methods for locating small metallic bottom targets (such as struts from CRX-7) to aid in that search.