YES

After renaming modulo { a->0, s->1, b->2 }, 
it remains to prove termination of the 4-rule system
{ 0 0 1 1 -> 1 1 0 0 ,
  2 2 0 0 2 2 1 1 -> 0 0 2 2 1 1 0 0 ,
  2 2 0 0 2 2 2 2 -> 0 0 2 2 0 0 2 2 ,
  0 0 2 2 0 0 0 0 -> 2 2 0 0 2 2 0 0 }


The system was reversed.

After renaming modulo { 1->0, 0->1, 2->2 }, 
it remains to prove termination of the 4-rule system
{ 0 0 1 1 -> 1 1 0 0 ,
  0 0 2 2 1 1 2 2 -> 1 1 0 0 2 2 1 1 ,
  2 2 2 2 1 1 2 2 -> 2 2 1 1 2 2 1 1 ,
  1 1 1 1 2 2 1 1 -> 1 1 2 2 1 1 2 2 }


Applying the dependency pairs transformation.

After renaming modulo { (0,true)->0, (0,false)->1, (1,false)->2, (1,true)->3, (2,false)->4, (2,true)->5 },
it remains to prove termination of the 32-rule system
{ 0 1 2 2 -> 3 2 1 1 ,
  0 1 2 2 -> 3 1 1 ,
  0 1 2 2 -> 0 1 ,
  0 1 2 2 -> 0 ,
  0 1 4 4 2 2 4 4 -> 3 2 1 1 4 4 2 2 ,
  0 1 4 4 2 2 4 4 -> 3 1 1 4 4 2 2 ,
  0 1 4 4 2 2 4 4 -> 0 1 4 4 2 2 ,
  0 1 4 4 2 2 4 4 -> 0 4 4 2 2 ,
  0 1 4 4 2 2 4 4 -> 5 4 2 2 ,
  0 1 4 4 2 2 4 4 -> 5 2 2 ,
  0 1 4 4 2 2 4 4 -> 3 2 ,
  0 1 4 4 2 2 4 4 -> 3 ,
  5 4 4 4 2 2 4 4 -> 5 4 2 2 4 4 2 2 ,
  5 4 4 4 2 2 4 4 -> 5 2 2 4 4 2 2 ,
  5 4 4 4 2 2 4 4 -> 3 2 4 4 2 2 ,
  5 4 4 4 2 2 4 4 -> 3 4 4 2 2 ,
  5 4 4 4 2 2 4 4 -> 5 4 2 2 ,
  5 4 4 4 2 2 4 4 -> 5 2 2 ,
  5 4 4 4 2 2 4 4 -> 3 2 ,
  5 4 4 4 2 2 4 4 -> 3 ,
  3 2 2 2 4 4 2 2 -> 3 2 4 4 2 2 4 4 ,
  3 2 2 2 4 4 2 2 -> 3 4 4 2 2 4 4 ,
  3 2 2 2 4 4 2 2 -> 5 4 2 2 4 4 ,
  3 2 2 2 4 4 2 2 -> 5 2 2 4 4 ,
  3 2 2 2 4 4 2 2 -> 3 2 4 4 ,
  3 2 2 2 4 4 2 2 -> 3 4 4 ,
  3 2 2 2 4 4 2 2 -> 5 4 ,
  3 2 2 2 4 4 2 2 -> 5 ,
  1 1 2 2 ->= 2 2 1 1 ,
  1 1 4 4 2 2 4 4 ->= 2 2 1 1 4 4 2 2 ,
  4 4 4 4 2 2 4 4 ->= 4 4 2 2 4 4 2 2 ,
  2 2 2 2 4 4 2 2 ->= 2 2 4 4 2 2 4 4 }


The system was filtered by the following matrix interpretation
of type E_J with J = {1,...,2} and dimension 2:

0 is interpreted by
 /   \
| 1 1 |
| 0 1 |
 \   /
1 is interpreted by
 /   \
| 1 1 |
| 0 1 |
 \   /
2 is interpreted by
 /   \
| 1 1 |
| 0 1 |
 \   /
3 is interpreted by
 /   \
| 1 1 |
| 0 1 |
 \   /
4 is interpreted by
 /   \
| 1 1 |
| 0 1 |
 \   /
5 is interpreted by
 /   \
| 1 1 |
| 0 1 |
 \   /

After renaming modulo { 0->0, 1->1, 2->2, 3->3, 4->4, 5->5 }, 
it remains to prove termination of the 8-rule system
{ 0 1 2 2 -> 3 2 1 1 ,
  0 1 4 4 2 2 4 4 -> 3 2 1 1 4 4 2 2 ,
  5 4 4 4 2 2 4 4 -> 5 4 2 2 4 4 2 2 ,
  3 2 2 2 4 4 2 2 -> 3 2 4 4 2 2 4 4 ,
  1 1 2 2 ->= 2 2 1 1 ,
  1 1 4 4 2 2 4 4 ->= 2 2 1 1 4 4 2 2 ,
  4 4 4 4 2 2 4 4 ->= 4 4 2 2 4 4 2 2 ,
  2 2 2 2 4 4 2 2 ->= 2 2 4 4 2 2 4 4 }


The system was filtered by the following matrix interpretation
of type E_J with J = {1,...,2} and dimension 2:

0 is interpreted by
 /   \
| 1 1 |
| 0 1 |
 \   /
1 is interpreted by
 /   \
| 1 0 |
| 0 1 |
 \   /
2 is interpreted by
 /   \
| 1 1 |
| 0 1 |
 \   /
3 is interpreted by
 /   \
| 1 0 |
| 0 1 |
 \   /
4 is interpreted by
 /   \
| 1 1 |
| 0 1 |
 \   /
5 is interpreted by
 /   \
| 1 0 |
| 0 1 |
 \   /

After renaming modulo { 5->0, 4->1, 2->2, 3->3, 1->4 }, 
it remains to prove termination of the 6-rule system
{ 0 1 1 1 2 2 1 1 -> 0 1 2 2 1 1 2 2 ,
  3 2 2 2 1 1 2 2 -> 3 2 1 1 2 2 1 1 ,
  4 4 2 2 ->= 2 2 4 4 ,
  4 4 1 1 2 2 1 1 ->= 2 2 4 4 1 1 2 2 ,
  1 1 1 1 2 2 1 1 ->= 1 1 2 2 1 1 2 2 ,
  2 2 2 2 1 1 2 2 ->= 2 2 1 1 2 2 1 1 }


The system was filtered by the following matrix interpretation
of type E_J with J = {1,...,2} and dimension 9:

0 is interpreted by
 /                 \
| 1 0 1 0 0 0 0 0 0 |
| 0 1 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
 \                 /
1 is interpreted by
 /                 \
| 1 0 0 0 0 0 0 0 0 |
| 0 1 0 0 0 0 0 0 0 |
| 0 0 0 1 0 0 0 0 0 |
| 0 0 1 0 1 0 0 0 0 |
| 0 0 0 0 0 1 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 1 |
| 0 1 0 0 0 0 0 0 0 |
 \                 /
2 is interpreted by
 /                 \
| 1 0 0 0 0 0 0 0 0 |
| 0 1 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 1 0 0 |
| 0 0 0 0 0 1 0 1 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
 \                 /
3 is interpreted by
 /                 \
| 1 0 0 0 0 0 0 0 0 |
| 0 1 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
 \                 /
4 is interpreted by
 /                 \
| 1 0 0 0 0 0 0 0 0 |
| 0 1 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
 \                 /

After renaming modulo { 3->0, 2->1, 1->2, 4->3 }, 
it remains to prove termination of the 5-rule system
{ 0 1 1 1 2 2 1 1 -> 0 1 2 2 1 1 2 2 ,
  3 3 1 1 ->= 1 1 3 3 ,
  3 3 2 2 1 1 2 2 ->= 1 1 3 3 2 2 1 1 ,
  2 2 2 2 1 1 2 2 ->= 2 2 1 1 2 2 1 1 ,
  1 1 1 1 2 2 1 1 ->= 1 1 2 2 1 1 2 2 }


The system was filtered by the following matrix interpretation
of type E_J with J = {1,...,2} and dimension 9:

0 is interpreted by
 /                 \
| 1 0 1 0 0 0 0 0 0 |
| 0 1 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
 \                 /
1 is interpreted by
 /                 \
| 1 0 0 0 0 0 0 0 0 |
| 0 1 0 0 0 0 0 0 0 |
| 0 0 0 1 0 0 0 0 0 |
| 0 0 1 0 1 0 0 0 0 |
| 0 0 0 0 0 1 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 1 |
| 0 1 0 0 0 0 0 0 0 |
 \                 /
2 is interpreted by
 /                 \
| 1 0 0 0 0 0 0 0 0 |
| 0 1 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 1 0 0 |
| 0 0 0 0 0 1 0 1 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
 \                 /
3 is interpreted by
 /                 \
| 1 0 0 0 0 0 0 0 0 |
| 0 1 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 0 0 0 0 0 0 0 0 |
| 0 1 0 0 0 0 0 0 0 |
| 0 1 0 0 0 0 0 0 0 |
 \                 /

After renaming modulo { 3->0, 1->1, 2->2 }, 
it remains to prove termination of the 4-rule system
{ 0 0 1 1 ->= 1 1 0 0 ,
  0 0 2 2 1 1 2 2 ->= 1 1 0 0 2 2 1 1 ,
  2 2 2 2 1 1 2 2 ->= 2 2 1 1 2 2 1 1 ,
  1 1 1 1 2 2 1 1 ->= 1 1 2 2 1 1 2 2 }

The system is trivially terminating.