If that was true, the spoilers would have started shipping in January as their most recent quarterly financial statements closed on 12/31/18. They could have shipped literally every spoiler owed on January 1, 2019 and it would have not impacted what they said on yesterday's earnings call. Plus, since they are a public company and must use GAAP accounting, the liability for spoilers owed needs to be reflected when each car was sold -- not when they ship the spoilers. So, while it MIGHT have been a cash flow play (i.e. order the spoilers and pay for them in THIS quarter rather than Q4, 2018), the liability would have still needed to be on the books AND given their likely cost per spoiler (has to be less than $500), I don't think they'd monkey around with their financial statements to save such a small relative amount of cash.
All of that said, I hope you are right about them starting to deliver all of them now -- for whatever reason!!