If you manually Opt Out a Contact, they will receive a message saying: 

"You have been manually unsubscribed. Please reply with 'START' to opt back in to receiving messages from this number"

If you wish to opt a Contact back in to texting, you can Request Opt In for Phone Number and they will receive this message:

"Please reply with 'START' to opt back in to receiving messages from this number"

And if a Contact opts themselves in by texting you 'START' they will receive an automated message saying: 

"Reply STOP to unsubscribe. Msg & Data Rates May Apply."

If you have any further questions about this, please reach out to Support at nextsupport@textus.com.

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