I've booked a trip to NYC with Emirates. Because of the fact I have some points expiring in April I've booked a fare business that allowed to ask for upgrade to first using points. This fare was not the lowest but to use points this was the one to book.
Now they upgraded me on the return flight but not on the ongoing one (that will be in a week). First class is still empty cause I tried to book 6 seats on the flight and there is availability.
What are your suggestions to obtain the upgrade even on the first flight? I don't want to throw miles away and booked with them only to spend these miles.

Thanks for your help.