Answer
Before making changes, print out what you have in case you make a mistake

Call Redirection By Time of Day and Day of Week changes where you HUNT and FDN depending on time of day it is and what day it is.  There are multiple steps to implement the feature, explained in the books or here (Includes both Time of Day and Day of Week sections)

In summary, you will need to define:

• LD 15 RDR_DATA: Specify Redirection Times and Days (up to four different schedules)
• LD 10 / LD 11: CLS RTDA (Redirection by Time and Day Allowed)
• LD 10 / LD 11: ARTO (Schedule 0,1,2,3 for this TN)
• LD 10 / LD 11: AFD, AHNT, AEFD, AEHT (DNs where calls go during alternate schedule)

Link to this page: http://www.ghtrout.net/rdr/rtda.html