When I put those dates into Excel 9/24/2014 + 2550 = 9/17/2021
Your dates are 2549 days.
Another aspect is in looking at 3 different Jewish calendars on both those years all agree that the Eve of Trumpets is 9/24/2014 and Eve of Day of Atonement is 9/15/2021.
The distance between those dates is 2448 days.
The first-half of the 70th Week of Daniel is 1,260 days, and the second-half is 1,290 days totaling 2,550 days in length. If the
70th Week were to begin with the 'covenant with many' on Rosh Hashanah Sept. 24, 2014 during the lunar tetrad of 2014-15 it would conclude 2,550 days later on Day of Atonement/Yom Kippur Sept. 16, 2021.
I believe that the '70th Week of Daniel' will begin on 'Feast of Trumpets' and conclude seven years (2,550 days) later on the 'Day of Atonement'.
Come Lord Jesus!