You want to make a bet that neither of these cars will be in volume (>100,000) production by the end of Q1 2019?
Let's put your sales expectations into perspective. 100,000 production by Q1/2019 you say? I guess you mean annual production?
Audi e-tron Sportback will not be out until sometime in 2019, so it will definitely not be shipping much anything in or by Q1/2019. So it would be up to Audi e-tron quattro, a fairly large premium SUV to sell that during a partial year, since it is expected to launch sometime in 2018. It will not have reached its full production by Q1/2019 I think, so it would have to acccomplish that through a partial year.
Global sales of current cars might give us some indication. Audi sells 1,8 million vehicles a year - up almost a million from decade ago, so impressive figures. Out of those Audi Q7, the closest current car to Audi e-tron quattro, sold 102,200 units in 2016, doubling its sales from the previous year - a rare feat related to a new model.
The next closest competitor to the Audi e-tron quattro, Tesla Model X, sold 25,000 units in 2016. So no, I don't think taking that bet would be wise, nor would is it a usable indicator of pretty much anything.
But I will say this, if Audi e-tron quattro concept's production version is not in real, volume production by Q1/2019, I will have been wrong and I will freely admit it. Real, volume production for a car such as this means it is actually orderable, at relatively normal delivery times (3-6 months, assuming normal demand), at a normal price-point relative to Audi's normal range, in many of Audis markets. I would accept this happening in Germany and several European markets as being in volume production. The same, if it appears in the U.S., but I would not consider that a requirement - many of Audi's cars only appear in Europe and U.S. ramping up year(s) later is normal.
I would not consider Audi R8 e-tron type of sales of under 100 cars at 1 million a pop as being in volume production. Volume production means actual production lines pumping out these cars to regular customers in regular markets.
What I do expect to see is a smattering of Golf and A3 BEVs
They will not be coming out of the same platform as being shown here, though. The platform thinking and progress of a company such as VW are the real news here. What they whip up over that platform to wet appetites is irrelevant, the platform underneath - the text in the press-releases, not the pictures, so to speak - is the real progress here.
Yes, we will see more e-Golfs and A3 e-trons also (from other platforms), but for the Tesla type of large-battery vehicle, I believe higher-end Audis such as discussed here will VW groups first serious entries. Maybe they will surprise with a Bolt competitor, who knows, but I am not counting on it personally. Model X and Model Y competition is where it will be at first, I estimate.