There is no equivalent to "3 yo kinder" in Qld anymore. You can certainly have children in day care at any age, and there are also some private kindys that take younger children. But the majority of kindys in Brisbane are C&K, and are community run and do a one year program. They only accept children who are between 3 1/2 and 4 1/2, so that is the children who's birthdays are between July 1 the year before, and the first day of school term are 4 when they start. The children whose birthdays are from end of Jan until June 30 of the school year are 3 when they start and turn 4 in the first half of their kindy year. Then prep is one year later than that. So for my boys:

DS1 born Feb 2005 - kindy (pre-prep) in 2009, school (prep) in 2010
DS2 born Sep 2006 - kindy (pre-prep in 2011, school (prep) in 2012.

Does that clear it up.