Fair enough if you were privy to inside information, and without getting into semantics as to what is a 'long time ago' in your original post.
It seems it has only been officially announced in the last day or two as per CabinCrewe's post. Flights had been showing departing MAN for LAX on Mon/Wed/Fri as I recall.
MAN's US offering is looking decidedly thin in terms of destinations for next summer with EI only operating to JFK & MCO but not BOS as well.