** Shares of Dollar Tree DLTR.O ticked up 1.3% to $122.70 premarket

** The discount retailer replenishes its share repurchase authorization to about $2.5 billion, including any amounts remaining under pre-existing program

** Says it repurchased $500 million of its common stock in June as part of a block trade involving selling stockholders, and that DLTR had about $700 million remaining under its then $2.5 billion authorization after that transaction

** Up to Wednesday's close, stock has fallen 1.5% YTD