I am unsure about what the question is about.
Either, if it's about the challenge checker-map where one can see if it has a checker or not, it should be updated instant.
Otherwise, if it's like Target interpeted. It depends on when the checker is run for you. Since there are thousands of users of Project-GC, and the average checker takes a second or so. It will not be run for everyone right away. But a manual run will save the result and be used on the map.