Regarding the two fee structures the Council doesn't need to gazette it or specifically notify affected trades. They are only required to publicly notify it. As I said previously most Councils do it as part of their annual plan which gets advertised and therefore meets the requirement to publicly notify. Its the document which outlines their financial position and costings for the next year.
They could do it separately and advertise it more specifically to the people it most affects but why would they? It means another round of consultation, more advisers, more lawyers, more cost and if I was to be sneaky I'd say they might end up with opposition to their proposals, which they can avoid by putting it with other changes. Its easier to hide if its in a large document. The DBH, the PGDB and other large organisations operate the same way unfortunately. You can't challenge them on it because they've complied with the law.
My advice would be to find out where and when they advertised these changes and look out for them next year. Then make a submission. This is how the law works unfortunately
A PS1 is a design statement saying that a design complies with the Building Code.
A PS2 is a peer review statement issued by someone if they've been requested to do a review of someone else's design. Often done on large construction jobs to check that the structural design doesn't have any errors. It will normally be an engineer reviewing another engineers design work. The engineer will certify the other engineers design as complying with the Building Code.
A PS3 is a construction producer statement advising that work haas been done in accordance with the Building Code. Normally issued by tradespeople and can be requested for work not seen by a Council. Its the Councils decision whether to rely on one of them or not. Some Councils ask for testing statements. These are examples of PS3s. If a fault develops the writer of the PS3 is liable.
A PS4 is a construction review statement normally given by an engineer. Its his final word that his design has been followed and that a building complies with his design and the Building Code.