Glad that it worked for you! Since it did, I think there are 2 possible explanations to the leak. 1 is that you flooded the atomizer. As I mentioned before, this can be from puffing too hard or to much, or possibly from just using too much juice while priming.
The other way that I think it could have leaked was from having the coil not seated well. Maybe the coil's o-ring was wonky, or maybe it just wasn't snug enough into the base.
As i mentioned, the base can hold a bunch of fluid so it can just accumulate there over time until the tank is tipped just right and it comes out of the air holes.
Glad this is resolved! Have a good day!