https://wccftech.com/nvidias-geforce-rtx-2070-and-2060-will-hit-the-shelves-by-end-of-october-early-november/

So I have an update, I recently talked to an AIB and they gave me the timeline they expect the RTX 2070 and the XX60 card to hit the shelves by. NVIDIA always launches cards in pairs so even if the company announces the complete lineup at the event tomorrow, I am pretty sure we will only see the RTX 2080 Ti and the RTX 2080 hit the shelves anytime soon. I am also working on getting a supply schedule to get a better understanding of when the cards will be available after launch. Considering these are the AIB expectations of when they will send out shipments, they are prone to change without any further notice.

According to my source you are looking at two cards being seeded immediately after the event tomorrow: namely the RTX 2080 Ti and the RTX 2080. The RTX 2070 and 2060 may be announced at the event but their shipments will not begin until the end of October/early November at the earliest.  It goes without saying that realistically, whatever supply NVIDIA and its partners have prepared for the RTX 2080 Ti and 2080 will sell out in a few minutes after launch.