However, at the actual production rate of 500 cars (which began in late February) they would have delivered a minimum of 2,000 additional cars by the end of the quarter, with another 500+ in process.
Here is what George Blankenship wrote on March 21st -
During the past three weeks we have averaged MORE than 500 Model S DELIVERIES per week, and it looks like we’ll be setting another record this week.
Again, 3000+ cars were delivered by March 1st. You can see the acceleration that week, which would correspond to the first week of the three that Blankenship is referring to. He refers to another record for deliveries anticipated for the week he wrote the blog.
If you do the math, Tesla would have delivered 4,500+ cars by the end of that week. They still would have had a
full week still remaining in March, at a time when they are flowing 500+ deliveries per week.
Every line of evidence points strongly towards Tesla delivering more than 5,000 cars in Q1 and your concern only addresses one of those lines of evidence.