Robertie suggests that blue should slot 5/4 while white's board is not threatening. But why would we want to give white an opportunity to step to the edge of our prime with tempo? Didn't make any sense to me. The two white checkers are pretty well hemmed in even if we don't complete the perfect prime anytime soon.
  White is Player 2
score: 0 pip: 129  Unlimited Game Jacoby  pip: 134 score: 0
Blue is Player 1  
XGID=bCCBBBcAbbBbca:0:0:1:41:0:0:1:0:10 
Blue to play 41 
1.  Rollout^{1}  13/8  eq: +0.980 
 Player: Opponent:  76.03% (G:10.98% B:0.31%) 23.97% (G:3.40% B:0.05%)  Conf.: ± 0.003 (+0.978...+0.983)  [100.0%] Duration: 36.2 seconds 

2.  Rollout^{1}  13/9 6/5  eq: +0.962 (0.018) 
 Player: Opponent:  74.81% (G:11.14% B:0.38%) 25.19% (G:3.70% B:0.06%)  Conf.: ± 0.007 (+0.955...+0.969)  [0.0%] Duration: 2 minutes 16 seconds 

3.  Rollout^{1}  13/9 5/4  eq: +0.929 (0.051) 
 Player: Opponent:  74.59% (G:13.50% B:0.49%) 25.41% (G:4.76% B:0.11%)  Conf.: ± 0.006 (+0.924...+0.935)  [0.0%] Duration: 2 minutes 04 seconds 


^{1} 2592 Games rolled with Variance Reduction. Dice Seed: 67453503 Moves: 3ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10
The rollout with the cube where it should be:
  White is Player 2
score: 0 pip: 129  Unlimited Game Jacoby  pip: 134 score: 0
Blue is Player 1  
XGID=bCCBBBcAbbBbca:1:1:1:41:0:0:1:0:10 
Blue to play 41 
1.  Rollout^{1}  13/8  eq: +0.543 
 Player: Opponent:  76.76% (G:11.26% B:0.40%) 23.24% (G:3.08% B:0.05%)  Conf.: ± 0.003 (+0.539...+0.546)  [100.0%] Duration: 7 minutes 15 seconds 

2.  Rollout^{1}  13/9 5/4  eq: +0.513 (0.030) 
 Player: Opponent:  74.99% (G:13.83% B:0.58%) 25.01% (G:4.36% B:0.09%)  Conf.: ± 0.004 (+0.509...+0.517)  [0.0%] Duration: 8 minutes 33 seconds 

3.  Rollout^{2}  13/9 6/5  eq: +0.500 (0.042) 
 Player: Opponent:  75.17% (G:11.19% B:0.41%) 24.83% (G:3.63% B:0.06%)  Conf.: ± 0.005 (+0.495...+0.505)  [0.0%] Duration: 3 minutes 28 seconds 


^{1} 5184 Games rolled with Variance Reduction. Dice Seed: 67453503 Moves: 3ply, cube decisions: XG Roller
^{2} 2592 Games rolled with Variance Reduction. Dice Seed: 67453503 Moves: 3ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10
We might think about slotting if white has a decent prime of her own. We don't mind being hit here that much since it only improves our timing.
  White is Player 2
score: 0 pip: 135  Unlimited Game Jacoby  pip: 134 score: 0
Blue is Player 1  
XGID=bCCBBBAbbbbbBba:1:1:1:41:0:0:1:0:10 
Blue to play 41 
1.  Rollout^{1}  13/8  eq: +0.377 
 Player: Opponent:  70.60% (G:10.84% B:0.37%) 29.40% (G:4.70% B:0.12%)  Conf.: ± 0.003 (+0.374...+0.380)  [100.0%] Duration: 16 minutes 47 seconds 

2.  Rollout^{1}  13/9 5/4  eq: +0.369 (0.008) 
 Player: Opponent:  70.04% (G:12.13% B:0.50%) 29.96% (G:5.25% B:0.16%)  Conf.: ± 0.003 (+0.366...+0.372)  [0.0%] Duration: 18 minutes 25 seconds 


^{1} 10368 Games rolled with Variance Reduction. Dice Seed: 46178346 Moves: 3ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10
51 and 61 variants suggested by Stick:
  White is Player 2
score: 0 pip: 129  Unlimited Game Jacoby  pip: 134 score: 0
Blue is Player 1  
XGID=bCCBBBcAbbBbca:1:1:1:51:0:0:1:0:10 
Blue to play 51 
1.  Rollout^{1}  13/7  eq: +0.532 
 Player: Opponent:  76.50% (G:10.75% B:0.37%) 23.50% (G:3.07% B:0.04%)  Conf.: ± 0.005 (+0.527...+0.537)  [100.0%] Duration: 3 minutes 29 seconds 

2.  Rollout^{1}  13/8 5/4  eq: +0.518 (0.014) 
 Player: Opponent:  75.13% (G:13.92% B:0.61%) 24.87% (G:4.52% B:0.09%)  Conf.: ± 0.005 (+0.512...+0.523)  [0.0%] Duration: 4 minutes 10 seconds 

3.  Rollout^{2}  13/8 6/5  eq: +0.495 (0.037) 
 Player: Opponent:  75.11% (G:10.91% B:0.41%) 24.89% (G:3.84% B:0.08%)  Conf.: ± 0.007 (+0.487...+0.502)  [0.0%] Duration: 1 minute 42 seconds 

4.  Rollout^{2}  20/14  eq: +0.475 (0.056) 
 Player: Opponent:  74.03% (G:14.61% B:0.65%) 25.97% (G:6.79% B:0.19%)  Conf.: ± 0.008 (+0.467...+0.484)  [0.0%] Duration: 2 minutes 06 seconds 


^{1} 2592 Games rolled with Variance Reduction. Dice Seed: 46178346 Moves: 3ply, cube decisions: XG Roller
^{2} 1296 Games rolled with Variance Reduction. Dice Seed: 46178346 Moves: 3ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10
  White is Player 2
score: 0 pip: 129  Unlimited Game Jacoby  pip: 134 score: 0
Blue is Player 1  
XGID=bCCBBBcAbbBbca:1:1:1:61:0:0:1:0:10 
Blue to play 61 
1.  Rollout^{1}  20/13  eq: +0.533 
 Player: Opponent:  76.75% (G:9.93% B:0.33%) 23.25% (G:3.22% B:0.04%)  Conf.: ± 0.007 (+0.526...+0.540)  [100.0%] Duration: 1 minute 54 seconds 

2.  Rollout^{1}  13/7 5/4  eq: +0.512 (0.021) 
 Player: Opponent:  74.98% (G:13.95% B:0.61%) 25.02% (G:4.70% B:0.11%)  Conf.: ± 0.007 (+0.505...+0.520)  [0.0%] Duration: 2 minutes 00 second 

3.  Rollout^{1}  13/6  eq: +0.495 (0.038) 
 Player: Opponent:  75.11% (G:10.80% B:0.43%) 24.89% (G:3.54% B:0.05%)  Conf.: ± 0.007 (+0.487...+0.502)  [0.0%] Duration: 1 minute 47 seconds 

4.  Rollout^{1}  13/7 6/5  eq: +0.494 (0.039) 
 Player: Opponent:  75.02% (G:10.42% B:0.38%) 24.98% (G:3.40% B:0.04%)  Conf.: ± 0.007 (+0.487...+0.501)  [0.0%] Duration: 1 minute 39 seconds 


^{1} 1296 Games rolled with Variance Reduction. Dice Seed: 46178346 Moves: 3ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10