This is a bit gamey but it happened to me legitimately last night so thought I'd share it. May be of interest particularly to the cert starved or newbies...

At the end of an alert you get XP/certs regardless of which continent you're on. If you happen to be on a significantly underpopulated (by your faction) continent you get bonus XP. Since alerts draw much of the overall server pop the other two continents are often underpop'd. So at the end of an alert, say last two mins when you can't cap anything else anyway, hop over to the quiet continent and get more XP.

It's a bit unsporting but last night I couldn't even get to Esamir and was stuck on Amerish where we were getting +50% XP. Oh well...