Moderator: United Airlines
Join Date: Jun 2007
Location: SFO
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Eastbound out is nighttime flight
West bound return is a 90 minutes longer and daytime flight
For jetlag and best adjustment to destination, I would try to sleep on the outbound. Arriving in Europe in the morning is a killer time adjustment and best to stay awake till the evening (naps on arrival are a bad idea)
So, depends on if the upgrade is for sleeping or if experiencing the cabin and seat is the objective.