Valve body and transmission problem 727

Hello all, i recently cleaned out my valve body and noticed this notch in one of the passage ways, looks like someone drilled it was wondering if that could cause an internal leak?
I also have been having a problem with 1st gear locking up and releasing, trans also doesn't down shift when coming to a stop, never had any of these problems till I replaced the low/reverse band and rear drum, thanks for any input, it's a 75 dodge w100 if that matters

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