This depends on your subscription. During the free trial period and for the basic subscriptions, you’ll get assistance on weekdays from 8am untill 7pm. Outside this period, on the weekends at official holidays, your contacts will be redirected to the iReachm voicemail. This is a basic voicemail (“the person you are trying to reach is not available, please leave a message after the tone”). You can easily customize this by recording a voice message and send it to firstname.lastname@example.org
You also have the possibility to deactivate and activate the service in the iReachm app. Therefore, go to Menu > Settings > Service on/off. The marked hours represent when the assistance is active. Click on them to deactivate the service temporarily.