As I recall the cards were issued over 2 or 3 years. I'm pretty sure the "set" was started in 2006 with cards depicting home runs 1- 101. The next set of 100 (102- 201) were included in the update set. The cards continued with another 100 in Series 1 of the 2007 set and another 100 in the Series 2. Cards 402- 501 were in the Update set. The final 35 cards, 502- 536 were an insert/ subset in the 2008 Topps set.
I'm going by memory here and may be wrong, but pretty sure it was something like that.
I notice the site here has all 536 cards listed in the 2006 set. I know they weren't all put out at the same time.
Hope that helps.