You can init a new VMF range and have the new range as scratch volumes.
Sample init deck:
CONTROL COMPANY=(YOUR TLMS
RNN.n COMPANY NAME )
CONTROL AUX=00500 WARNING=000450 MESSAGE=Y SCRATCH=Y
The parm of SCRATCH= would be set to Y. This will init the VMF as scratch volumes. The VMF restore that follows will update the older volumes. The new volume range will be ready for use after the VMF restore.