I believe the photo to be taken sometime btween mid-Novermber 2003 and Early December 2003.
Big Thunder down 9/2003 - 8/2004
Xmas Decorations traditionally November through 1st wek of January
Mark Twain Rehab 11/3/2003 - 2/2004
And I find a
trip report to DL on 11/17/2003 that mention Space Mountain appears white from Main Street and unpainted from Tomorrowland
Don't know when painting was completed, but I recall it didn't stay 2-toned for long.