It's time to change your egg-hatching strategy in Pokemon GO.
Previously, it was reported that blue incubators hatched eggs more quickly than the permanent incubator. This is no longer the case. The orange incubator and blue incubators hatch eggs at the same speed now. There are two important things to consider about your incubators. Are you prioritizing egg turnover or are you prioritizing mileage?
If you have few incubators, you should be prioritizing mileage. Use your orange incubator to hatch the lower eggs and your blue incubators to hatch the larger eggs. If you use your blue incubator to hatch a 2km egg instead of a 10km egg, you will lose 8km when it breaks. However if you use the orange incubator, you can continue hatching eggs without losing an incubator. In some cases, you will just have 5km eggs. Because purple eggs are rare, it probably doesn't make sense to save your incubator, but it depends on your luck.
If you have lots of incubators, the strategy would be the same unless you have several 2km eggs. Generally, it's a bit wasteful to use up one cycle of your incubator on a green egg, but if you're trying to clear out your inventory for more purple eggs, simple prioritize hatching the green eggs with all incubators. This option generally only would apply to power users that have paid money for lots of incubators.
What's your strategy for hatching eggs in Pokemon GO?