We use Twilio as our SMS provider.
Merchants who have setup SMS Alerts will receive SMS Alert messages from up to 4 different originating phone #s.
Up until August 2018, we used to have only 1 originating phone #.
After August 2018, we have the 4 originating phone #s. This is a recommendation from Twilio to keep our phone #s from being blacklisted.
"In the United States, it’s typically recommended that you add one long code number for every 200 unique recipients per day (because long codes are intended for person-to-person traffic). For example, if your SMS technical support number typically exchanges messages with 1,000 people a day, you should add 5 phone numbers to your Messaging Service."