@Bigbruiseral - when I called DL the person on the phone didn't know what it was so they checked with a supervisor who asked if it made a physical difference to the car or just software. When I replied that it was just software they said OK, it would be noted on the policy.
Churchill (part of the same group as DL) said they would apply the same as DL once I informed them & it's mentioned on my policy alongside the 19" alloys & tow bar.
Both were perfectly happy that this is a standard manufacturer software upgrade (similarly Tesla also reduced 0.5 sec 0-60 as part of a previous fleet wide software upgrade). The software specification of all Teslas changes regularly so every vehicle is technically different to its 'as manufactured' state.