On page 8 of the following document
http://pdf.secdatabase.com/141/0001214659-16-012757.pdf
It says:
"Production Plan. Gino Raffin, our Vice President of Manufacturing and Product Launches, and Doug Frick, our Plant Manager
of Shreveport operations, have developed the production plan and facility layout. The facility layout has been developed to utilize the
existing infrastructure and flexible design of the buildings at the Shreveport facility. A detailed 47-week launch plan has been developed,
which includes 25 weeks of pre-production activities, 10 weeks of manufacturing validation and training, and 12 weeks9 of increased
production to reach optimal production output. Incorporated into the launch is the plan that the first 100 vehicles produced will be sold
to a fleet customer to provide feedback."
The "9" after the work weeks is a subscript at the bottom of the page which says:
"9 12 weeks to reach steady state production with one shift; 23 weeks to reach steady state with second shift."
Originally their plan was to reach maximum steady state production with one shift (500 per day) in 45 days (6 weeks). Then they would switch to two shifts and both shifts would be at steady state production in an additional 45 days (6 weeks). Thus they would ready 1000 vehicles per day in 90 days (3 months or 13 weeks).
(The 500 and 1000 vehicles per day is what EM said in the past. Perhaps these have changed also.)
Either they have revised their production ramp-up rate, or they are being very conservative because it is a legal document.