How to schedule call forwarding and how to define forwarding delay?

Features code for call forwarding:

Forward on no answer:                   61

Forward if not reachable:               62

Forward on busy:                             67

Forward unconditional:                   21

Format: **(CODE)*+(Number)# 

Example: **61*+3247123456#

To set the forwarding delay (5s/10s/15s/20s/25s/30s):

Format: **(CODE)*+(Number)**(delay)# 

Example: **61*+3247123456**30#

Note: to forward call to voicemail, use +32475181851