Can't answer because the poll doesn't include the correct answer, namely, "There is no "should" for leveling up."
When you have the XP, you level up. If you an do that in 2 sessions? Kudos! If it takes you five months of games? That's all good too.
There is no and absolutely should be NO expectations of levels after "X" sessions or "hours of game time" or any other ridiculous, meaningless, completely arbitrary count/number when a player becomes "due" a level.
Get the XP. Level up.
Well that's a completely meaningless, ridiculous, arbitrary statement for the many people who don't even use xp.