With the new aircraft ( 787-9 and A350 ) joining in the upcoming years, Turkish Airlines is increasing IAD, LAX, ORD and SFO frequencies and all these routes would be operated 10 times a week. This is the new rumor that I have read in 2 other forums and in addition to this, I have heard from an insider. However, no details of the schedule yet. AFAIH [ H stands for heard ], the additional flights would be morning flights that depart at similar times as TK3.
Turkish Airlines had operated x10 weekly to IAD and x11 weekly to LAX back in 2016 but after the political situation in Turkey, the additional flights were removed several months after being introduced.
Just a reminder that currently there is no credible source for a frequency increase and TK hasn't filed anything yet related to this in their S20 schedule.
This was the schedule when TK operated the extra frequencies to IAD and LAX back in 2016.
TK177 IST0640 – 1110IAD 333 247
TK007 IST1340 – 1810IAD 333 D
TK178 IAD1240 – 0555+1IST 333 247
TK008 IAD2325 – 1640+1IST 333 D
TK013 IST0940 – 1335LAX 77W x16
TK009 IST1420 – 1815LAX 77W x4
TK014 LAX1655 – 1600+1IST 77W x16
TK010 LAX2125 – 2030+1IST 77W x4