I think it's a difficult question to answer without knowing the full [or at least more details of your system] eg is it purely form based...or it mathematical...a combination of both...or something else I haven't considered.

My feeling is that anything with a heavy form component really needs a full year to expose you to all elements of racing....large fields, small fields, fresh horses, sour horses, wet tracks, dry tracks, good races, bad races, top jocks, other jocks, big trainers, small trainers etc etc

Mathmatical or statistically based methods...I'd still be saying 3 - 6 months minimum...ideas/systems/plans are all good for profit when you look at the early results but it's the longterm that gradually finds you out.