I don't know the general stand where TVX and TAC are concerned, but I liase abit with the BBFC when shooting for Liquid Gold. Their take on it: Cumshots are allowable as long as its anywhere on the body except the face.
Interesting when you think a movie like Silence Of The Lambs was passed when Jodie Foster had spunk thrown at her from a nutter in a cell, but I guess she ducked so it didn't count. This means to me that cum shots are okay if not implied in a gratuitous sexual manner. Psychos whacking off and chucking their custard in Hollywood movies is acceptable for TV (unless it was cut). Warped thinking there if you ask me.