NW tries to sell as many revenue seats per flight that they can.

Award seats are not necessarily available on every flight, for example the Tuesday and Wednesday before Thanksgiving will have most flights always sell out. There may not be many flights with standard award seats offered because NW will try and sell them first (and they will sell out) and no additional standard award seats will be offered on these dates.

Usually close to date of departure additional award seats will be released. For example, a redeye flight DTW/LAX might have 0 standard award seats available for April and then show a lot of availability for a flight 6 days out because the a/c has 40 empty seats and is not selling well.

RC