I think that depends on the ABV and the strains of yeast that you used. If you used something with a 11% tolerance, and both of those meads are there, then you'll need to add something with a higher tolerance, like ec-1118. Look at the yeast chart at gotmead.com
Now, the 1.045 will be pretty sweet, probably too much so, so if you take another measurement and it hasn't changed, then get another yeast. the 1.020 might be done, if I remember correctly that's on the semi-sweet to sweet end of a finished mead. Are you looking for some sweetness or do you want to take it to dry?
I am trying for a semi sweet. Used a Champange yeast (red Star ) Only reason I asked is because when I made the near identical mead last time and used Wyeast Sweet Mead Yeast it finished lower. Now that I look at my notes more closely these numbers may be a result of recent additions of fruit etc a few monthes back.