how to change the date of an event's execution in scheduler ?

[Mohamed Vall El Alem <Mohamed.Vall.El.Alem@crm.mot.com>]

Hi ns community,

May someone tell me if it is possible to modify the instant of execution
of an event already scheduled. I have the identifier of such event, and
it is scheduled via the "at" command;

Many thanks in advance for any suggestions.

Mohamed Vall EL ALEM
  Paris