The switch of the Log can not be executed because the file LOG is locked by CFT.  
If CFT is stopped, it can not restarted because the two logs are full.

Before V241, the LRECL of the Log file was 132. Since the V241, the LRECL is 256.   If you did not leave the default value in the macro CFTLOG and you had coded LRECL=133, in this case, it necessary to modify the LRECL with value 256