Made what feels like a total rookie mistake just a few weeks ago: Had nicely negotiated a much needed period of annual leave with my work to take a 'little' First trip to the US, in my calculations adding what I thought is the usual 'extra day' on the way back due to the time zones. But I didn't realize that with QF8 from Dallas leaving around 10pm Texas time, it's actually +2 days for the arrival.
And worst of it all: I only understood what was happening upon touchdown in Sydney which was after 2 straight bottles of Grande Dame which made for a VERY awkward conversation with my boss