Last night in a Little League tournament game I had a pitcher who ended the 4th inning with exactly 50 pitches. He pitched to the first batter in the 5th inning for two pitches, at which point I replaced him with another pitcher.

I thought the pitch count reverted back to the last pitch of his next-to-last batter, but the tournament director told me the pitch count reverts back to the FIRST pitch of the LAST batter.

So I thought his official pitch count would be 50, requiring 2 days rest, but
I'm told the official count is 51, requiring 3 days.

Does anyone know the answer? And can you point me to something in the little league rule book that clarifies it?

Thanks.