ZEV credit sales will better than last quarter, probably $200-$300 million, but I think Q4 is where Tesla's really going to sell a lot of credits.
This SA post is IMO pretty good overall, but I'm not as sure about total ZEV credit purchases matching last year's total of 130,000.
Tesla's ZEV Credits: Iceberg For Shorts, Life Boat For Longs - Tesla, Inc. (NASDAQ:TSLA) | Seeking Alpha
Based on the Q1/Q2 CA figures, Tesla is well ahead of where they were last year, and all of the other manufacturers combined have only reached roughly a third of their 2017 credit totals.
US Market Situation and Outlook (Rob Stark's American Megathread)
If the 3 takes as many plug-in sales away from other manufacturers as I think it will, they may need an additional 50k credits compared to last year. Or they can cut the prices on their plug-ins, but then they lose money on sales instead of via credit penalties, so that might be six of one/half dozen of another.