I hate leaving my checkers on the 24pt unsplit after my opponent makes an advanced anchor, but here we are way behind in the race and bar/21 gives us good chances of making an advanced anchor of our own anyway.
  White is Player 2
score: 0 pip: 154  Unlimited Game  pip: 182 score: 0
Blue is Player 1  
XGID=bEBAdDdeBA:0:0:1:64:0:0:0:0:10 
Blue to play 64 
1.  Rollout^{1}  Bar/21 13/7  eq: 0.538 
 Player: Opponent:  38.51% (G:8.25% B:0.31%) 61.49% (G:20.37% B:1.56%)  Conf.: ± 0.016 (0.554...0.522)  [99.9%] Duration: 31 minutes 58 seconds 

2.  Rollout^{1}  Bar/15  eq: 0.574 (0.036) 
 Player: Opponent:  38.02% (G:7.27% B:0.33%) 61.98% (G:21.08% B:1.47%)  Conf.: ± 0.016 (0.591...0.558)  [0.1%] Duration: 32 minutes 25 seconds 

3.  Rollout^{1}  Bar/21 24/18  eq: 0.584 (0.046) 
 Player: Opponent:  38.04% (G:7.52% B:0.30%) 61.96% (G:22.93% B:1.40%)  Conf.: ± 0.016 (0.600...0.569)  [0.0%] Duration: 29 minutes 13 seconds 


^{1} 1296 Games rolled with Variance Reduction. Dice Seed: 271828 Moves: 3ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10
The following position looks like a manually created variant of the above position, but in fact these two positions arose naturally in two different games. Since I hadn't gotten around to studying the first position before the second position arose, I made the same play both times. Oh well. Here the extra builder on the 8pt makes 13/7 even more attractive.
  White is Player 2
score: 0 pip: 154  Unlimited Game  pip: 184 score: 0
Blue is Player 1  
XGID=bDCAdDdeBA:0:0:1:64:0:0:0:0:10 
Blue to play 64 
1.  Rollout^{1}  Bar/21 13/7  eq: 0.473 
 Player: Opponent:  40.15% (G:8.47% B:0.32%) 59.85% (G:19.79% B:1.51%)  Conf.: ± 0.017 (0.491...0.456)  [100.0%] Duration: 34 minutes 01 second 

2.  Rollout^{1}  Bar/21 24/18  eq: 0.524 (0.050) 
 Player: Opponent:  39.58% (G:7.41% B:0.31%) 60.42% (G:22.06% B:1.34%)  Conf.: ± 0.017 (0.541...0.507)  [0.0%] Duration: 31 minutes 41 seconds 

3.  Rollout^{1}  Bar/15  eq: 0.529 (0.055) 
 Player: Opponent:  39.18% (G:7.61% B:0.34%) 60.82% (G:20.51% B:1.30%)  Conf.: ± 0.018 (0.547...0.511)  [0.0%] Duration: 34 minutes 01 second 


^{1} 1296 Games rolled with Variance Reduction. Dice Seed: 271828 Moves: 3ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10