I'm sure they will get wildcards for the WTA tour events on grass plus Wimbledon(if they don't get in direct), so any one win in these events will be enough to preserve their rankings.
As of now, including 110 points this week ( so far! ) that takes Joss & Anna to 955 points, 560 from 6 counters from last year plus 395 from 5 counters this year.
The 6 from last year are :
115 due off 08/06
15 due off 15/06
180 due off 20/07
80 due off 27/07
110 due off 03/08
60 due off 19/10
So, yes, just the 115 points of significance in the grass season, but a lot in the following few weeks then not much really at all after 03/08.