I thought I was brilliant for figuring out the following, but see below for the proof that I wasn't as smart as I thought!
--- My first attempt to play Sherlock Holmes ---
At
oceanic-air.com, they show the date of the flight date as September 22 and a tiny calendar (attached below) that indicates it was a Tuesday, assuming it shows each week from Sunday to Saturday.
The last time September 22 was a Tuesday was in 1998. Before that, 1992, 1987, 1981, and 1970.
Dates on the wall diagram refer to 1981, 1984, and 1985, with the one in 1985 definitely in the past tense. So that narrows it to 1998, 1992, and 1987.
Which means, by the way, that Rousseau was on the island before the last markings were made on that diagram.
Below "I AM HERE" on the digram, the digits 4.08.00 and 8.15.01 and 01.06.05 are presumbably dates. 15 can't be a month, and years wouldn't be shown with one digit, so the format must be m.dd.yy, meaning the dates are in 2000, 2001, and 2005, and the one(s) marked "COMPLETE SHUTDOWN IN EFFECT" are still in the future for the Losties.
--- Elementary, my dear Watson ---
My research above is wrong, because the
DriveSHAFT site (for Charlie's band) clearly answers the question!
So oceanic-air.com's calendar shows each week from Monday to Saturday, and I was completely off base above. Oh well, at least we now know the answer.
That still means that January 6, 2005 (01.06.05) is in the very near future (if it's really been about 60 days since they crashed), and that's the date marked "COMPLETE SHUTDOWN IN EFFECT".
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