Hi welcome to the club
Hope I can help you as I have slimiar case as you .
1)I am also 1 of the mummy who direct latch but I will make sure I must pump 1time in the night before sleep make sure is clear .
My massage lady told me the same things too to pump every 2 to 3 hours to prevent block duct and increase milk supply .
I have quite a lot of milk too but all kept in deep freezer it can be kept up to 6months ,it will sure of cause increase you supply but no harm you can use it for baby bath it's good for their skin
2)Yes, you should pump out as the milk will actually reproduce every few hours if you never pump out it won't have space for the reproduce milk and soon you will have milk ducts and it will slow down your milk too .
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