We all know what the M25 can be like. Can get stuck for a long time so want to make sure I have plenty of battery.
Assuming 20 minutes charging, and a further 5 - 10 minutes detouring there and back - if you are held up in traffic you skip the charging and use that extra contingency to catch your flight, but have to suffer charging on the return. If you make good time you use up that dead time charging before you go.
Charging before you go (warm battery) will be faster than on return (in Winter a cold battery will charge slower - driving to a more distant Supercharger would warm the battery before you got there)
But, yeah, its one situation where charging is a bit of a pain. Although ... here's my Man Maths in case any use to you?! ICE is, say, 10 minutes a week to detour, fill, queue to pay - that's 8 hours a year. 2x 20 minute charges a month is the same ... actually, better, as you can use the 20 minutes for Emails that you would have to do when you get home, so time-neutral. If driving across Europe drive-charge-drive-charge the 20 minute break every couple of hours is good. But Must-Charge is an inconvenience.
resist the temptation to check the app
IME that wears off! O/P could get TeslaFi, that will let the car [deep] sleep but will still get some figures (there is a "Wake Up" command if you do, actually, need to do something). It records Stats for all sorts of stuff (rear left seat heater on/off for every minute since you first owned your first Tesla!). For someone If you are addicted to the APP I reckon you'll be far more addicted to the data from TeslalFi (or similar APP)
I posted some screenshots of TesalFi years ago (i.e. latest version has a lot more "stuff"). I recommend you don't install it just before going to the airport - you do need to get the SLEEP settings correct, so allow some elapsed-time to make sure that is working as expected, otherwise TeslaFi will be checking the car often and cause phantom-drain. Referral code increases the trial period from 14 days to a month. You can use my UserName if you don't have a mate's code to use.
I don't know about you but we're enjoying a proverbial Indian Summer here in sunny West Herts today, but it will be cooler tomorrow and winter is only a few weeks away. I've not yet experienced Tesla driving in cold weather so I'm curious as to how much range loss we can expect in low single...
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