Let consider following scenario.

Suppose an ODUk SNCP is configured from Station A to B and type is SNC/N.

Active path: A-->C-->B (electrical regeneration/cross-connection at Station C)
Protection path: A-->D-->B(electrical regeneration/cross-connection at Station D)

C has Subrack 0,1,2&3 and cross-connection is at Subrack 3 of Station C.
Now suppose Subrack 3 of C is out of communication

In that case if fiber break occurs between Station A to C, will service switched to path A to D?  

Waiting for answers.

Dear Tanjil Ahmed,
  Thank you for your share.
   In that case if fiber break occurs between Station A to C, the  service will switched to path A to D.
  The ODUk SNCP can be switched normally between station A to B when the master subrack has abnormal communication with the slave subrack at station C.
Alice

As Alice says, yes the services will be rerouted to protection path once reported the R_LOS and ODUk_PM_AIS.