I'm in no way an accountant or anyone suitable to provide advise, but I'm seeking advise from my accountant when he returns from leave.
I've read the description on the ATO website, and it is written in a language I'm never going to understand. It appears this new rule has been snuck in without any fanfare or explanation. Ambiguous is a word I don't use often, but there are too many statements I can't follow.
If you are registered for GST, you add 10% to the cost of the product you are supplying. At the end of a 3 month cycle, you pay the collected GST to the ATO, via your BAS statement. So the consumer is really paying the GST, as a GST registered business, you are simply collecting Tax for the ATO. Anything you buy, or are supplied, is returned via your business tax return.
This new rule appears to prevent Australian Businesses and consumers from buying overseas GST free for any amount. Aimed at multinationals, that are making profits, but not paying Tax in Australia. Luminaries such as the idiot at Harvey Norman, have been championing the cause, as online overseas purchases are affecting his bottom line. Poor Multimillionaires. My heart bleeds. It not like anyone would buy a mattress or wall unit "on line". Once the list of these idiots is posted, I'm boycotting their products. The mark up alone on their products is the sole reason we go overseas for products !
There is a confusing criteria regarding the import of $75,000. So is that from one overseas supplier to one Aussie business ? Is it $75,000 from that O/S supplier to all Aussie Businesses ? How does the ATO know how much the O/S supplier sells to Australians ? No O/S business is going to register with the ATO.. When 3 months has elapsed, can the O/S supplier claim back the GST from the ATO ?
It does not create more jobs. There's already massive delays out of customs, often imports are in customs longer than the time taken to arrive from O/S. The jobs should be filled now..
I don't know how it will affect RTBB or APR. But my opinion is that the ATO and Aussie Government are making consumers pay for taxes they were too scared to ask the Multinationals for (Mining companies..) for the last 10 years.

I don't know the answers, but sneaking this up on Aussie Small Business in such a covertly manner is typical.