Speed execution for accelerating

What is the sequence of my turn here?

I am currently in a BOOST state, I send an ACCELERATE command, still in a speed of 15.
I then hit 3 mud patches reducing my speed down to 6, the next round reflects my speed as 6, is this intended or should my speed be 8?

round:91
player: id:1 position: y:1 speed:15 state:USED_BOOST boosting:true boost-counter:5 powerups: OIL:6, BOOST:11
opponent: id:2 position: y:1 x:450 speed:8

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Completed round: 91

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Starting round: 92

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round:92
player: id:1 position: y:1 speed:6 state:HIT_MUD boosting:false boost-counter:0 powerups: OIL:6, BOOST:11
opponent: id:2 position: y:2 x:457 speed:6

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Similar example where speed is 8 (below the max speed), I hit a mud patch and speed in the next round is 8

round:94
player: id:1 position: y:2 speed:8 state:TURNING_RIGHT boosting:false boost-counter:0 powerups: OIL:6, BOOST:11
opponent: id:2 position: y:1 x:467 speed:3

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[░░░░░1░░▓░░░░░░░░░░░▓Φ░░░▓]
[░▓░░░░░░░Φ▓▓░░░░░░▓▓Φ░░░░░]
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Completed round: 94

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Starting round: 95

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round:95
player: id:1 position: y:2 speed:8 state:HIT_MUD boosting:false boost-counter:0 powerups: OIL:6, BOOST:11
opponent: id:2 position: y:1 x:469 speed:3

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