For the really popular local kindies which this original thread was referring to, it is best to apply exactly 1 year ahead, otherwise the chance of getting in is really slim.
For example, St. Catherine at Kowloon Tong would announce on their website by each autumn the method of obtaining an application form by mail, and the window usually lasts less then 2 weeks. If you miss the cut off date, there is no way you can even get an application in, even if you know and go talk to their ex principal (happened to a friend of mine once). Of course, you cannot apply earlier either.
Many local kindies require that the parent go and line up for the application form. The queues usually are so ridiculously long, that my brother actually took a photo and sent it to me last year. Therefore, for those wanting to go the local pretiguous path, expect and be ready for the application battle in September.
Yup, K1 is the mass intake, although many schools do have pre-nursery now (please check each target school ahead of time), and a very few only starts at K2 (such as CCKG).