Yes, it is. WhatsApp Business distinguishes between conversations started by your business and conversations started by the customer. When you start a conversation with your customer, you are limited to pre-approved message templates. Whenever your customer starts a conversation or replies to your message template, a 24-hour support window opens during which you can communicate freely with your customer. These messages are called session messages, and the 24-hour window resets every time you receive a new reply from the customer.