That is correct you have 28 days to appeal their decision
You will need to contact the law society of NSW and get a referral to solicitors that practice in Planning law or Land and Environment.
You should also contact council and get copies of the application and the decision and is possible minutes of the meetings relevant to this development.
You should be able to get that under the old Freedom of Information Act now called GIPA.
Law society contact page is as follows
The link on getting information from the council is below.
All the best and good luck with it.
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