When Modl Revised General Skilled Migration Legislative Changes, Effective Date?

General Skilled Migration Legislative Changes, Effective Date? - when modl revised

If the immigration authority of the changing requirements for skilled migration to Australia, MODL occupations migrants (in Demand List) - Advertisements are usually published on the website of DIMIA. I expect some changes in the list that may affect my application, I do not have all the requirements I need. Who knows when these changes take effect? For example, if the Updated 15 February 2009, no changes are effective immeadiately? There is fulfilled within a specified period of time to fulfill - like at a certain time? Please help.