Interesting report and thanks for sharing.
I cant quite make out the type of beacon on the photo but I found this from an aaib report about a 406 MHz beacon...G-BYSA the accident in this report happened at 1015 and the first rescue asset was sent at 1108!
The pilot’s PLB was equipped with a 406 MHz transmitter, which is detectable by satellites of the Cospas-Sarsat Programme. In order to determine an approximate position of the activated beacon, more than one satellite pass was required.
At 1036 hrs, a downlink from a satellite pass alerted the UK Aeronautical Rescue Co-ordination Centre (ARCC) to the activation of the beacon. A further satellite pass at 1056 hrs was required to resolve the beacon’s location in the approximate area of the accident. The ARCC attempted to contact the beacon’s registered owner (the pilot) and made further enquiries, to determine the nature of the incident and decide on the appropriate response1. At 1108 hrs, a land-based Coastguard rescue team was tasked to the area of the accident. This was followed later by the deployment of RNLI lifeboats and a SAR helicopter.
The ARCC commented that GPS-enabled PLB’s will generally allow much quicker location of the transmitter than those without this capability. Additionally, the more information and, in particular, contact details that owners include when registering a PLB, the quicker the ARCC can respond and the higher the probability of them deploying the correct rescue assets.
Additional information on what happens when a PLB is activated can be found at
www.cospas-sarsat.int/en/
so, unless you either make and have received a mayday call or have a GNSS enabled beacon AND someone to answer the registered phone number and say (s)he is flying to the Channel Islands... then don’t expact anything to happen quickly.