If I leave the infotainment on or the door open whilst vacuuming or moving the seats back and forward, the message in the dash comes up after only 15 odd mins. I usually switch off the interior lights. This happened last week after a 250 mile round trip the previous day, with a fully charged battery. Am beginning to think that it's just a cautionary early warning as the car turns over no problem. Had same issues in the D4 and Fl2. Seems very sensitive to any electrical fluctuations, hence the quick warnings.
Mind you I can have the TV/DVD running for an hour with no warnings in my car whilst cleaning inside with no issues

MY17 First Edition - 3L Diesel Td6 - Farallon Black - Roof rails,side steps,tints,tow bar,mudflaps,door strips.
MY18 Hse Luxury - 3L Petrol Si6 Supercharged - Santorini Black - Roof rails,side steps,tints,tow bar,mudflaps,door strips,22's,dynamic pack 1,bonnet vents,t.v,dual view,frontcooler,360°camera,rear cooler/warmer,roof vane,black LR badges,wade sensing,door sill plates,boot liner, solar screen,wind deflectors,service plan,tracker,speed camera detector,dual dash cameras,ceramic coating.