To whom it may concern...
As I have already completed the entire 3-Year Liturgical cycle for the responsorial psalms for Sunday Mass, and also the responsorial psalms for a significant number of Solemnities and Feast days, you can usually find new additions to the present collection if you notice that the psalm version is ver. 2 or higher. For example:
Ps50AshW1.pdf - from the present collection
Ps50AshW2.pdf - new addition