Is it possible to send an SMS or MMS message from a server through a service such as Twilio and set the source 10 digit number as desired?
For example, a delayed message system where someone wants to send a text at a scheduled time, they would enter their phone number, the message, destination number and target delivery date & time.
That information is stored on the server, then, at the specified time, sent through a service such as Twilio. The desire is the recipient should receive the message just as they would have if it was just sent by the sender direct.
The desire is to allow the recipient to respond back to the originator of the scheduled message directly as if it was live in real time and not delayed.
Twilio developer evangelist here.
With Twilio it is only possible to send SMS messages using a Twilio number that you've bought or an alphanumeric sender ID, that is a string up to 11 characters long that starts with a letter.