We've done our best to ensure longevity and value for money when designing the Sun Bulb. The Sun Bulb's is rated to 30,000 hours, which is approximately 7 years with 12 hours of daily use.
Unfortunately the Sun Bulb's LED's are not replaceable. The LED chip is soldered onto the main fitting of the light, meaning it can't easily be swapped out. You would need a licensed electrician, and the new LED chip to be able to fix this, however the other components in the light would also be nearing their end of life at around this time, so it may not be worth it.
As an engineering led company, we're always working towards making future iterations of the Sun Bulb (and all of our products) replaceable as we strive to create more sustainable solutions for our customers and the environment.