I think the putty rd will be fine looking at the RFS maps and when you put your route in shows no incidents also here is a link
http://www.rfs.nsw.gov.au/dsp_content.cfm?cat_id=683 and when you scroll down the 2 Hawkesbury fires, 1 is being control and the other is controlled as of today though. I have sent a message to the Hunter RFS to ask the question for Sat and waiting for a reply if not ill ring them Friday.