It may just be that they are waiting until he is "old enough" to take the WISC. Maybe they don't have a WPPSI- plus, he would probably ceiling out. The WISC norms start at age 6. Honestly, I would probably just wait in order to get an accurate IQ result.
Great point about WISC IV being worth waiting for - much better test than WPPSI for a gifted 5 year old.
So my undated recommendation is to get a meeting started to outline the process for the gradeskip and start to fill out the Iowa Acceleration Scale, doing 'everything except the IQ testing' and then the minute he turns 6 get the testing and make the move to the next grade (you can always decelerate in September if the IQ scores come out very discouraging.)
If I remember correctly,according to Iowa, IQ scores aren't needed for an early enterance situation, which this isn't exactly, but pretty close.
Does anyone have the details fresher in their minds?
Grinity