Yes you may schedule the email to be sent on a different date or time. 

This option under the promotion tab you may select SMS and as per the red arrow is shown , you can set schedule to schedule the SMS blast. 

You may select the date and time on when the SMS should go out.

Once the date and time have been set, click the send  button to set a scheduled SMS blast. 

The SMS blast will be sent out as per scheduled.