I'm sure there is some reason that our system is set up this way but I have no idea of what it is... Anyway here is what SHOW PUBLIC_LIB gives:

From To Type Index#
88400 88426 PUBLIC_LIB 427
6000 6425 PUBLIC_LIB 0
498 498 PUBLIC_LIB 426

498 is apparently our MODEM. Since we used to have extension number only up to 425 maybe the installer put the modem (which we don't use) at 426. Anyway the 88400 series contains some voice mail entries that duplicate our old extentions somewhat with some unassigned entries. So being a PBX neophyte I'd be tempted to change 88401 to do VM for x426 or some such.

Thanks for your help, as I said our local rep won't return our calls, too busy or just standard business manors for this town sigh.