Hey mate, yeah agree with Andre's comments - If you reverse calculate the $20bn based on my projections, they'll hit it before 2022. The good thing is, even at $20bn GMV there is still so much opportunity especially in-store in the US which runs at about US$4 trillion annually (not sure if that includes groceries though). Even if they're able to attract a few % of that, well, I probably don't need to say what the outcome will be. Plus there's additional markets and adjacent revenue streams (including the valuable data they are collecting). I'm keeping a very close eye on the competitors though.
Anthony and Nick are extremely conservative, so it's very likely that in their heads they're thinking they're gonna hit quite a bit above $20bn by 2022. Anyway, time will tell.