If you are consistently sending messages to the same set of recipients, then the logical process would be to define the topic once, add subscribers and then simply send the message to the topic each day.
If you wish to maintain your own list of subscribers, where people can add/remove themselves throughout the day, then use the features of Amazon SNS that let you send SMS messages directly, without going via a subscription.
From Setting SMS Messaging Preferences:
For Default sender ID, type a custom ID that contains up to 11 alphanumeric characters, including at least one letter and no spaces. The sender ID is displayed as the message sender on the receiving device. For example, you can use your business brand to make the message source easier to recognize.
Support for sender IDs varies by country. For example, messages delivered to U.S. phone numbers will not display the sender ID. For the countries that support sender IDs, see Supported Regions and Countries.
If you do not specify a sender ID, the message will display a long code as the sender ID in supported countries. For countries that require an alphabetic sender ID, the message displays NOTICE as the sender ID.
You can override the this setting when you send a message.
From Sending an SMS Message:
When you send a message, you can control whether the message is optimized for cost or reliable delivery, and you can specify a sender ID.
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AWS.SNS.SMS.SenderID
A custom ID that contains up to 11 alphanumeric characters, including at least one letter and no spaces. The sender ID is displayed as the message sender on the receiving device. For example, you can use your business brand to make the message source easier to recognize.
Support for sender IDs varies by country. For example, messages delivered to U.S. phone numbers will not display the sender ID. For the countries that support sender IDs, see Supported Regions and Countries.
If you do not specify a sender ID, the message will display a long code as the sender ID in supported countries. For countries that require an alphabetic sender ID, the message displays NOTICE as the sender ID.
This message-level attribute overrides the account-level attribute DefaultSenderID, which you set by using the SetSMSAttributes request.
