I haven’t personally worked with an ECO, but I have seen plenty of them in my current position. I have only noticed our company producing ECOs for product in the validation and post validation stages (once the design input and verification are completed). We implement ECOs for design/hardware changes and for packaging/labeling changes of our launched products. Depending on the complexity of the change request, ECOs typically take between 4-6 weeks to complete.

For example, currently one of the components in one of our products is reaching its end of life (EOL), meaning the manufacturer isn’t producing the product any longer (can be due to error or newer versions that are available). So after validating the new part will be equivalent to the part we currently use (which is reaching EOL), an ECO must be produced for that product. The ECO is completed by the legal manufacturer of the product. I say this because we have shared rights on some products with our partners, and if they are the legal manufacturer for some of the country registrations then they will need to complete the ECO process. Even when that occurs though, we always write our own ECO for our records parallel to our partner’s ECO, it just isn’t a critical path in the schedule.

Another example I have seen is for packaging and labeling changes. ECOs are needed each time a large packaging/labeling change is made. This can be for updating manufacturing addresses, customer service information, content and the addition of translations (typically caused from the addition of a country on a SKU or content changes).