There simply isn't on general rule of thumb. I always arrive between 9.30 and 10 30 am. Queue time before immigrations varied from absolutely none to >90 minutes  Too much dependencies to predict! 

I have always assumed that was true, but I arrived at noon last January and had a 50 minute wait in the immigration line.

The best Swampy advice is not to arrive at midnight for the EU rush hours. The lines can be horrible. After lunch is much calmer.

Umm can you spam your YouTube slop somewhere else?

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