In Arc Map TMA_Active_Phases only displays below 1:750

In Arc Map (9.2) TMA_Active_Phases only displays below 1:750. There are no parameters set in the scale range on the display properties in Arc Map. Is there a pre-set scale range in GIS0020 or GIS0010. I cannot see one and there is no reference in the manual.

We are wanting to sort before the final data pump for our move from 4.3 to 4.5.10