There is no such thing as "saver awards" and there is no such thing as "last minute saver awards".

There is no such thing as "dumping" awards.

It is rare for the price of award seats to come down; that said, the long summer holiday when business travel is almost non-existent is when availability may be better; that said, they can forecast demand with sufficient precision that ther should rarely be a need to reduce or "dump" awards at the last minute.

There certainly is no fixed routine whereby you can expect a certain point in time when the price drop may occur, if it ever happens at all.

Because you have only spoken in generalities I cannot go into any more detail. There is no overarching system of reducing award seat pricing at fixed deadlines prior to departure.