If you create a new component that has this export structure

MYCOMPONENT

Export options
[X] option A
[ ] option B
[ ] option C

Option A options
[X] all
[X] some
[X] top-rated

then the "Option A options" cannot be selected all at the same time. Only one is finally evaluated. Probably, the array is overwritten.

We must check how this affects the drush exports too.

Cheers.