Hi @Speedy-one
ACF does not come standard with a a time picker field, so I can’t provide support for a 3rd party developed field type.
In regards to it being a sub field, you can have a look here as to using sub fields in a WP_Query args:
http://www.advancedcustomfields.com/resources/how-to/how-to-query-posts-filtered-by-custom-field-values/#example-5
Thanks
E