Now that might be a bit of a furphy, mate. I know the Kiwilanders have their fair share of slang too. My brother married one and they are a weird mob.
I took a gander at our dictionary and assure can you mob means a large number of anything to quote directly from the dictionary
quote:
Range of application is much wider in Australia than elsewhere and one can talk of 'a huge mob of sheep, a nice mob of people or even a mob of sausages'.
Yes it is correct to say that To Knock up means to give a wake up call is a very nice polite way of saying that, 'someone is about to, or has taken pleasure in bringing a person back to their sense... usually by use of sudden impact to the moosh. (to knock ones block off their shoulder or said another way if you cannot make them see your point of view, make them see sense, you deck 'em i.e use physical means). The second application is usually understood when one is talking about a sheila (a female) meaning she is now in the family way. 
Alex
