Picking One of Two

My original plan was to run both Grasslands 50 and Hells Hills 50 but it looks like I will only be able to make arrangements to run one of the two.  I have a burning desire to defeat Grasslands (errr just finish) but I also want a WS qualifying time and only HH is on the list.  My desire to one day run WS out weighs my desire to finish Grasslands this year.