I first joined the HubPages ad program on February 26th of this year. With only one hub actually being an "earner," it took me eleven days to make my first dollar strictly through the HP ad program. Then, (insert ominous background music here) Google's unholy panda-penguin hybrid updates kicked in and it took me 53 days to clear my second dollar. Fortunately by the beginning of May things stabilized again and my third dollar only took 14 days.
Of course, relying on only one hub is not the ideal plan. Come June my schedule should open up so as to allow me to publish several hubs which I have presently crawling around assorted notes, napkins, and brain cells.