A couple of options:
1) Book past the expiration date in the HGVC system. As long as you don't cancel the reservation the points will not be lost.
2) Search RCI. There is HGVC points availability in NYC June 2018, HGVC District in Washington DC in Jan/Feb 2018 and and Fiesta Los Cabos for various weeks. Depends where you want to go. Again, if you book past the expiration date, as long as the reservation is not cancelled, the points will not be lost. If you need to cancel, you will lose the RCI reservation Fee of $230 plus a $59 fee to convert the points to RCI where you have 2 years to use them. You will need to call the RCI number to set this up using bonus points, otherwise the system will use club points.
Good luck!