The answer is that its a binary representation of the date

YYYYYMMMMDDDDDHHHHHMMMMMMSSSSS
101000011000101011010101001111

Where YYYYY = Number of days since 1980
MMMM = month 1= January etc
DDDDD = day of month
HHHHH = hours in 24 hour
MMMMMM = minutes
SSSSS = no of secs on 1:2 ration ie 30 secs is 15 here

Which leads to another question ... what happens to 2.6 when the year reaches 11111 = 1980+31 = 2011

so 12 years bang?