This is all explained in the blog post Sunsetting Construct 2. As noted there, we will only do essential bug fixes and compatibility updates until July 2021. Beyond that date there will be no further support at all.
Given that I was the sole developer ever working for Construct 2, and this is a similar support period that Microsoft provides for Windows with thousands of developers all over the world, I think this is a pretty reasonable life cycle for the product. If you still need active support and new features, you can upgrade to Construct 3, and you have about a year to work out any compatibility problems if any come up.