My rough estimate (based on personal experience) is around 30 or so games of sub-par ranked rounds, and quite a few scored matchplays (against higher tiers will certainly help a lot if you win, as Alosso had also explained above).
Be warned though, master tees are far more difficult (quite literally in fact) than the pro-to-tourpro transition (learnt this the hard way with cheap clubs all the way), so if I were in your position I'd take my time to join a lot of tournaments whilst still in the very experienced stage of the tour pro tier.
Best of luck!