how many resources can you see from the drop down menu?

[PCScheduler]

I have over 1,000 resources in my resource pool. When I have a schedule
linked to this pool but want to choose a resource that is past ID 1,000, it
doesn't show up in my drop down menu when assigining resources to a task. I
have to go to the resource pool, find out the ID, and enter it to assign the
resource I want.

Is 1,000 resources the max the drop-down menu will show? Is there a way to
change this?

Thanks.