My apologies, as most people posting in this thread generally are talking about business tax liabilities and your post didn't specify, I assumed. Nevertheless I'm not doubting yours or anyone else's advice per se, just suggesting everyone seek their own advice as tax can be a highly individual thing and penalties can apply for doing the wrong thing, whether intentional or not (as I'm sure we all know). I'm searching the private ruling register to see if it has come up before...
It's an interesting one because you could get into some grey areas quite quickly. What if you had a charge from Woolworths for $5, then you pre-loaded $100,000, paid ATO, next day bought a $5,000 couch, $3,000 fridge, etc. Could be argued you were prepaying/paying off other items on that same statement