Use D* in a UDM when you want the UDM to flag horses in races run on any dirt surface. This includes races run on the inner dirt course. It also includes races taken off the turf.
Use D in a UDM instead of D* if you want the UDM to flag horses in races that are carded for and run on the main or outer dirt course only. When D is used instead of D* the UDM will not flag horses in races taken off the turf.
Use d in a UDM instead of D* if you want the UDM to flag horses in races that are carded for and run on the inner dirt course only.
Use T* in a UDM when you want the UDM to flag horses in races carded to be run on a turf course that actually are run on a turf course. This includes races that are run on either the inner or outer turf course as carded. Note: T* does NOT flag horses in races taken off the turf and run on a dirt course.
Use T in a UDM instead of T* if you want the UDM to flag horses in races that are carded for and run on the main or outer turf course only. When T is used instead of T* the UDM will not flag horses in races run on an inner turf course. Note: T does NOT flag horses in races taken off the turf and run on a dirt course.
Use t in a UDM instead of T* if you want the UDM to flag horses in races that are carded for and run on the inner turf course only. When t is used instead of T* the UDM will not flag horses in races run on the outer or main turf course. Note: t does NOT flag horses in races taken off the turf and run on a dirt course.
Use O in a UDM instead if you want the UDM to flag horses in races that are carded for the turf but have been taken off the turf.
Hope I explained that in a way that makes sense.
Please re-read as I've edited what I posted earlier. Specifically: UDMs using T*, T, and t surface designators will not flag horses in races that have come off the turf.