Searching for long-term activation codes or "official" license keys for (now largely succeeded by Avast Premium Security) that claim to last until 2048 is a common pursuit for users looking to save on cybersecurity costs.
If you want the features of Avast Premier (Premium Security) without the risks of shady keys, consider these official routes: the key is blacklisted.
Avast frequently runs sales where you can get a year of protection for a significant discount (often up to 50-70% off), which is far safer than a leaked code. the key is blacklisted.
Stolen or leaked keys intended for large businesses. Once Avast detects they are being used by thousands of individual IPs, the key is blacklisted. the key is blacklisted.