Depending on what you read, we either have way too many or way too few cage free eggs at the moment. Here's from a USDA report on September 29, 2017 suggesting current pledges to go cage free are far outstripping the production of cage free eggs, resulting in a "shortage":
The shortage of cage free eggs mentioned by the USDA refers to the gap between the future promises and comments made by retailers and others to go cage free and the current level of cage free production. The oversupply of cage free eggs mentioned by Cal-Maine is referring to the gap between the current number of cage free eggs being produced and what the final consumers are currently willing to pay and buy.
At some point there will have to be a reckoning between the long term commitments by retailers to go cage free and the willingness of real-life consumers to cover the added costs of cage free eggs. Consumer demand will have to shift out as more cage free eggs come on the market, retailers will have to live with selling fewer eggs, or some of the cage free commitments will ultimately have to be receded.