That makes little sense. A new Production Suite is supposed to be being announced at NAB mid way through April which is dependant upon Tiger, that means pros will have a 2 month wait before the new product is in their hands. It would likely mean that Tiger is going to be announced at WWDC instead.
To be honest I would be suprised if anyone outside of apple's own retails stores know the date that 10.4 is coming. It isn't outside the realms of possibility that even the apple stores don't know. Looking at the latest Tiger builds and the bug fixes there isn't that much more to do, certainly not enough that it would take 3 months to put it right. However we are quickly running out of time for Tiger to reach Gold status and be ready for shipping mid April.