Spoiler
The best rollouts suggest that at normal scores, 24/20 13/8 is a bit better than 13/8 13/9. The first wins more games, but the latter wins more gammons (also loses a fraction more gammons). Personally I prefer 13/8 13/9 but that's mostly because I think it's better versus weak(er) opponents. At this matchscore I guess 24/20 13/8 is technically best as road (at 4-away) can use (doubled) gammons as well as we (behind in the score) can, but I voted 13/8 13/9 anyway as it's at least more interesting usually.
Spoiler
Those are the two moves I do with this opening roll, and have very little preference. 13-9, 13-8 feels slightly safer against a good opponent, so that will tip me that way in this match.