Originally Posted by
Wasabi Tofu
Or, refer very old XONEWCX rule.

Once upon a time, XONEWCX permited only one flight for a specific route and direction.
Well, we've come full circle, so to speak, from August 1:
Rule 4. (i) The same city pairs/sectors cannot be flown more than once in the same direction.
I just got caught on that rule, which makes embedding three NYC-BOS round trips in one DONE3 no longer feasible...