I am glad you asked the question.
The Truth is Bitmain built the L3+ back in October of 2016 they have been mining them almost 1000-1500Gh/s level for Litecoin for last 6 months.
If you don't believe me look at the 9 months difficulty chart here:
https://bitcoinwisdom.com/litecoin/difficultyYou will notice from October to March Hash Rate was rising roughly 1000 gh/s my initial calculation taking in account for existing Litecoin Hardware A2, A4 and a lot of other Asics including KNC cubes showed me that a lot of LTC miners were not profitable or marginally profitable so you noticed the hash rate stabilizing.
At that point Bitmain added L3+ to network and mined LTC they were collecting around 175-230k Litecoin per month and did so over 6 months Bitmain create a horde of over 1.2 Million Litecoin if they were to sell them at that point it would have crashed the market and they would have devalued there own hardware. Once they reached 3000gh/s (50% of network rate ) they started selling L3+ in batches 1st Batch shipping April 15th second on May 15th and 3rd on July.
At that point they already made 5x ROI by collecting 1.3 million LTC and now they will sell close 1200 L3+ at $1300 per piece collecting additional $1.5 million + $11 million in LTC they currently hold which they will slowly release back in the market covert it to BTC or (additional Alt currencies).
Do keep in mind that the analysis is speculative in nature and very far fetch to believe but the truth is all one has to look at is Actual number and its clear as day.
On a second note I have some contact in Chengdu that confirmed the fact that Bitmain have been expanding mining operation since october not sure if they were related to Bitcoin or Litecoin.