In this case, it's understandable that they need to improve their profitability, and laudable that they are not doing so by closed sourcing the product.
This is what OSI had to say about it: https://opensource.org/node/1099
"The Elastic projects were offered under the Apache license. Outside contributors donated time and energy with the understanding that their work was going towards the greater good, the public software commons. Now, instead, their contributions are embedded in a proprietary product. If they want to enjoy the fruits of their own and their co-contributors’ labor, they have to agree to a proprietary license or fork."
"Elastic’s current business model is inconsistent with what open source licenses are designed to do. Its current business desires are what proprietary licenses (which includes source available) are designed for."