The answer to 'lifespan of panel upgrade' is that a properly installed and maintained electrical panel can last 25-40 years on average. The lifespan of your panel upgrade will depend on factors like the quality of the components, how well it was installed, and how much electrical load is placed on it over time.
Older electrical panels from the 1950s-1980s may need to be upgraded sooner, often within 20-30 years, due to outdated technology and safety concerns. Newer, high-quality panels can often last 30-40 years or more with proper care. Regular inspections by a licensed electrician can help identify any issues and extend the lifespan of your electrical panel.