One can find data supporting any side of the situation one wishes to support.

 But P is very, very slow to move down, and very quick to tie up.

 So much depends on the method of application, the soil type and ph, the type of P, etc., etc. Some data says that banding P in a concentrated band tends to slow the soil tie up as the band reduces soil particle contact.

 The best way that I find on my fields to find the levels of phosphorus and their location, is to do a multi-level soil test sample. Like 0-2", 2-6" and 6-12". My fields that have been no-tilled for a few years have been showing stratification and the top 2" are quite a bit higher in P concentration, but we typically dry out the top 2" long before the crops bloom or joint.