+1. I try and switch my watch as soon as I board (or after I eat the meal on eastbound TATL) so that my sleep cycle feels real with the time zone I'm going (e.g., look it's already 2am in London so I'm sleeping and when I wake up it'll be morning).

And for the late night westbound TPACs since they arrive in the early morning, I stay awake for at least the first 2-3 hours if possible so that I can sleep for most of the second part of the flight (when it's nighttime where I'm going) and when I wake up, I can look at my watch and the local time is 4-6am which feels more natural and lets me hit the ground running