LEM,
Thats from a "combined" Classic/NG manual.
On the CFM56-3, the Maximum Certified
Physical Fan Speed N1 = 106% (5485 RPM) - like you said. Thats for all CFM56-3 engine models.
Depending on what model of the CFM56-3 you have, the Max TO, and Max continuous N1 will differ.
The -B1, -B2 and -C models all have the same core,
e.g. the higher rated -C engine will have a
higher max TO thrust (N1=96%) and the lower
rated -B1 will have a lower max TO thrust (N1=91%) at ISA.
Equally Max continuous thrust is N1=93% and
N1=89% at ISA.
So, I assume that max reverse thrust is similar
depending on engine rating.
What happens between 96% and 106% I don't know. I can only guess that the
engine gets inefficient and life-span gets dramatically shortened and it gets trashed if it has been beyond 106%
Cheers,
Morten