Our company holds a WPS for heavy wall 9 chrome dated in 2001, material P5B at that time.  What is required to use this procedure for heavy wall 9 chrome now, since the reclassification of the base material to P15E?  Have there been changes to the WPS essential variables that would require a new procedure & re-qualification?  Can the original PQR from 2001 support a new procedure written to reflect the classification change from P5B to P15E?
Thanks!