Buying items on ebay with a glut of supply

If there is a product you are looking into buying, and a seller has recently decided to sell 100+ of this item in individual auctions and increased the short term supply, what happens with the supply/demand dynamic?

Does demand actually increase, or does it stay the same since most people won’t even realize there is a flood of supply since the only people looking will not even know there is a glut of supply?

If you want to buy one of these items, does it matter when during the supply glut you buy one? Is it best in the beginning, middle or end?

Does the supply glut even lower prices since it happens over a short period (7 days) or is that period enough to make people start bidding lower and lower since they realize there are more than enough items to bid on later?