A carrier-run registry decides overnight which business texts get delivered

The enforcement path is what turns this into an operations question. Portman wrote that carriers now use AI to compare live messages against the samples a business submitted at registration ^[8], and that "even compliant campaigns can be filtered if traffic patterns raise flags" ^[9]. Before a line goes dark, traffic throttles and the delivery rate drops ^[10]. Portman does not say how a suspended line gets reinstated.

Quiet hours give a scheduler something exact to work with. Portman puts the window at 8:00 a.m. to 9:00 p.m. in the recipient's local time zone ^[16], which is 13 hours where the recipient lives. Send one list across the contiguous United States and the three-hour gap between Eastern and Pacific cuts the window everyone shares to 10 hours, 11:00 a.m. to 9:00 p.m. Eastern ^[1]. A 9:00 a.m. Eastern send arrives at 6:00 a.m. for a Pacific recipient ^[2].

Registration also ages. Portman writes that brands registered in 2023 or 2024 may need to reverify, because outdated registrations are a common filtering trigger today ^[12]. The failure he puts first is lane mixing: adding "By the way, refer a friend and get $20 off" to an appointment reminder makes the entire message marketing under carrier rules and the law ^[13]. Marketing has to run through its own registered campaign with its own opt-in ^[14].

The registry is not the only rulebook, and the state one runs on a decade-long clock. Portman says a STOP reply has to be honored immediately ^[17], and a Virginia opt-out received the month SB 1339 took effect is binding until January 2036 ^[3]. He also writes that a customer who handed over a phone number has not thereby agreed to receive texts, which is why documenting consent matters and why a purchased list of 10,000 numbers is a liability ^[20].

All of this comes from one interested party. Portman is the founder and CEO of Textdrip, a small business SMS tool that automates campaigns ^[1], and the Twilio figures reach the reader through his Forbes Tech Council post. A skeptic would say a vendor who sells campaign automation has a reason to foreground compliance failures, and the panic is his own framing: "Their texts stopped being sent, the campaign got flagged or the number was suspended overnight without any warning," he wrote ^[2]. The specifics he cites are the checkable part, including a rejection code, a sending window, two state statutes, and a penalty of up to $2,000 per violation for content issues such as phishing under Twilio's guidelines ^[11].