Some of the parked Aircraft are only due C checks and a couple are due overdue AD's so probably cheaper to fix these than keep getting other old 747 and putting on Register?
And if they cant afford to fix a 200F they have no chance of affording the spares on a 400F! although they will save 30% crew costs instead of 20% but loose the best crewmember!
Besides Mike got you a 748 already, unfortunately it has HS instead of B in front of it!