So all the votes are currently for Egypt. Given recent topics posted and posts made in this thread attacking Eygpt after securing the Middle Easr and moscow just makes sense. It’s where your units are and building a sea lion fleet late game is off the table. Landing in London against a skilled opponent at any point in the game seems to actively harm efforts in the East and makes your units more vulnerable to US counterattack.
Therefore I would say that sea lion is a purely opportunistic move.