Bokonon
Title-customizing Member
Theory #1: AWD in the 6-9 months from 24 Mar 2017:
24 Sep 2017 - 24 Dec 2017
AWD not until next year.
Theory #2: AWD in the 6-9 months from 1 July 2017:
1 Jan 2018 - 1 Apr 2018
AWD not until next year.
*snip*
#1 is less likely than #2 because the dates 24 Sep 2017 - 24 Dec 2017 don't match the "AWD not until next" year statement.
This has been heavily litigated in the AWD thread (albeit with no definitive conclusion).
The problem I see with this common interpretation is that the tweet on which it is based does not clearly address whether it is answering the "dual motors" or "go fast" part of the original question. If Elon's answer pertains to the "go fast" part of the question, then it is consistent with his later tweet that the Performance configuration would be available about a year from now (where "now" = March 24, 2017).
The tweet about AWD going to production in 6 to 9 months did not specify an anchor point, but as others have pointed out:
(1) the colloquialism "in [n] [unit of time]" almost always implies "from now" unless otherwise qualified (e.g. "the train departs at 7:00, meet me at the station in 5 minutes" means to meet 5 minutes from the current time, not at 7:05)
(2) his tweet about the Performance configuration explicitly specified "a year from now", so, in the absence of any other qualifiers, the most logical assumption to make is that "in 6 to 9 months" also refers to "from now".
So, based on this reasoning, and the summer timeline for RHD models being on the road in the UK, I think your original interpretation of the timeline (theory #1) is actually more likely to match Elon's intentions.
RWD: Production starts in July 2017
AWD: Production starts sometime between October 2017 - January 2018*
P AWD: Production starts in April 2018*
* Dates rounded up by a week for simplicity
Of course, at the end of the day, we're speculating about the timeline for an all-new product and manufacturing process with a lot of unknowns. I fully expect that this timeline (and our understanding of the factors driving it) will change within the coming weeks.