The following is the Feb. 9, 2021 Congressional Research Service report, Navy John Lewis (TAO-205) Class Oiler Shipbuilding Program: Background and Issues for Congress.
From the report
The Navy procured its first John Lewis (TAO-205) class oiler in FY2016, and a total of six have been procured through FY2021, including the fifth and sixth in FY2020. The first six TAO-205s are being procured under a block buy contract that was authorized by Section 127 of the FY2016 National Defense Authorization...
https://news.usni.org/2021/02/12/report-to-congress-on-john-lewis-class-oiler-program