The time on Casio publicity photos is always 10:58 and 20 seconds. The date is always Sunday, 6.30.
A partial theory:
The hours had to be 10,11, or 12 because it would look better than a single digit number. 12 is an awkward number because of people using / not using the 24-hour clock (which also rules out 13 - 23), and 10 looks better than 11.
One of the minute numerals had to be an 8, to make maximum use of the digit segments. 5 translates into digital form better than most numbers, which may explain why it's 58 rather than, say, 28.
I don't have a theory for the seconds or the date...