Is this paper on CFA Institute website up-to-date?

This paper indicated that if a company capital structure is expected to change over time, assuming a stable WACC for FCFF model is not reasonable and the paper offered a remedy called Adjusted Present Value (APV) method (Page 20)

This paper was published in 2005 and I am wondering if it is still keeping up-to-date, CFA Institute website still keeps it displayed though.

It looks like the concepts are still very relevant.