Being on free television instead of pay makes a huge difference, being able to watch Australia's tour to South Africa or most matches of the World T20 (I think the finals, if we make them, would be on Gem) costs you a $74 a month subscription to Foxtel, that's buying DBC14 every single month of the year (which is a better way of spending the money).
The Ashes and Big Bash on the other hand are on free to air TV, so everyone in the country can (and pretty much did with the record ratings) watch, instead of the 30% that have pay television here.
I don't subscribe to Foxtel, which means all I can do in the winter months is just see short highlights packages - not follow along with the tour (some of it is on radio, but that's not as good).
It doesn't mean everyone forgets about cricket, but it isn't anything like the Summer months of local cricket.
That said, I don't think the specific matches being played at the time of release will factor at all into their release timing and their history of maintaining prices in the market will mean it won't matter to them when someone wants to play a cricket game.