Just been searching to try to find out?
IPEC was purchased from Mayne Nickless in 1998 by Toll Holdings and renamed Toll IPEC.
And this was when the new *&^%$#@! owners suddenly sold the DC9s and I, and many others were out of work again.
Really stupid (sad) thing was they were very good aircraft, IPC and IPF, yet they apparently never flew in the USA, just sat in one of the graveyards.