When you send a message to a non hike user, it gets delivered as an SMS. The number that is displayed is hike VMN (Virtual Mobile Number). However, your name is also displayed so that the recipient knows who sent the message. So you will always come to know who that hiker is who is welcoming you to join the awesome world of hiking!! :)
For hike2SMS messages you get a message will be denoted as 'SMS' instead of tick and double tick. Thus a message state SMS for your hike2SMS messages means your messages might have already delivered!
However, if you get a response that the recipient is on DND waiting for reply, Click here for for more details: