500 hours is the only restriction mentioned in LASORS with respect to ZFT.
The requirement is for six landings to be completed,
including at least one full stop landing. In the case of
an application for a multi-pilot aeroplane; an applicant
who has logged more than 500 hours experience on
multi-pilot aeroplanes of similar size and performance,
this requirement may be reduced to a minimum of four
landings in the aircraft.