What requirement states that promotions must be communicated at an appropriate time?

The requirement that promotions must be communicated at an appropriate time is categorized as a standard regulatory requirement. This ensures that promotional activities are transparent and not misleading, allowing consumers enough time to consider their options. Regulatory bodies emphasize the importance of timely communication so that clients are informed and can make educated decisions without pressure or confusion, particularly in financial services where timing can significantly impact a client's choice and understanding.

In contrast, discretionary guidelines may suggest best practices but are not required or enforced regulations. The notion that there is no requirement overlooks the established rules governing promotional communication. Similarly, limiting this obligation to unsolicited calls does not capture the broader regulatory landscape, which applies to all promotional communications regardless of the method used. Thus, the correct answer underscores the importance of adhering to regulatory standards to promote fair and ethical conduct in communications.