What counts as a MapKitJs call?

MapKitJS offers 250,000 free map calls per day at the current time (June 2021). This raises the question for me: What is counted as a call?

Is the call counted when the mapkit.init(...) method is called or when a new map instance is created?

For example, if I create two maps on my website with the methods:

const map1 = new mapkit.Map(container1, { ... } );
const map2 = new mapkit.Map(container2, { ... } );

but only call mapkit.init(...) once, does that still count as only one call or two?