There are a number of important facts to consider when...

There are a number of important facts to consider when considering the impact of shipments to China.
Firstly, your statement that it is a large market but constrained by shipping capacity is not correct, currently the China slaughter market for exports from Australia does not really exist, there has only been one consignment of approx 170 head delivered under the slaughter protocol by Elders
The health protocol is onerous (and as a result adds cost) when compared to other Asian slaughter markets.
There are a numbers of regulatory and operational constraints applied to the Chinese importers by the Chinese authorities which impact on the ability to use large vessels
The China market has proven to be very price sensitive in respect of breeding imports previously and will be similar for slaughter imports. The current Australian prices at farm gate are not conducive to being able to trade with an acceptable margin in respect of slaughter cattle compared to other export markets (ie Indonesia & Vietnam)
There are still many hurdles to overcome before this market actually takes any volume of substance, the media hype surrounding the signing of the protocol in July 2015 is far different from the reality of the situation.