I ordered 4 units of L3+ from Bitmain on July. They should deliver me form 21.9. You can count that around 10,000 devices will be plugged in in October which will rise difficulty for around 5000. I think they received orders in August too which will ship in October. I think you can count you will get 50% from what you see now in calculators in November. Other factor is price which was going up from 45 to 90 USD but now after China ICO ban and rumors that China will ban Crypto exchanges it drops to 65 USD. I hope price of Ltc will go to 100 but can not guarantee that. Bitmain has Dash machine D3 which shows crazy good result in calculators of mining profitability but with that D3 you must also count that there will be difficulty increase with every new wave of orders. If I didn't buy 4 L3+ devices I would order D3. About Litecoin you can see profitability here: https://www.cryptocompare.com/mining/calculator/ltc?HashingPower=504&HashingUnit=MH%2Fs&PowerConsumption=1200&CostPerkWh=0.075.