RULE 55. STARTING TIME.     (a) Crews may be started later than bulletined starting time according to service conditions and time will commence at time required to report for duty. Conductors and brakemen will not be required to hold themselves in readiness for an earlier call than prescribed in the bulletin.  

     (b) Crews assigned to local, mixed, or combination switch and road service will be allowed 100 miles for service performed in advance of bulletined starting time at rate applicable to class of service performed, except as provided in following paragraph (c).  

     (c) When crews assigned to local, mixed, or combination switch and road service are brought on duty in advance of bulletined starting time for extra road service, time will be computed from time required to report for duty for the extra road service until released therefrom, with minimum allowance of 100 miles and new day will begin when brought on duty for regular assignment.