The answer on fleet number is no one really knows. Except that I know for sure there are 13 744Fs, just flown the newest baby not too long ago myself.
As for the 744 pax fleet, probably still 30 over?? Definitely winding down with quite a few flown to storage north of LAX. SQ is not certain of the decision in winding down completely of the 744s cos 777s do not really give that sort of substitute that they want for high load sectors.