In March 2019, the Trump Administration released its Fiscal Year 2020 Budget Request for NASA. This budget did not include any money for the Block 1B and Block 2 variants of SLS. It is uncertain whether these future variants of SLS will be developed.  Several launches previously planned for the SLS Block 1B are now expected to fly on commercial launcher vehicles such as Falcon Heavy, New Glenn, Omega, and Vulcan.  However, the request for a budget increase of $1. 6 billion towards SLS, Orion, and crewed landers along with the launch manifest seem to indicate support of the development of Block 1B, debuting Artemis 3. The Block 1B will be used mainly for co-manifested crew transfers and logistical needs rather than constructing the Gateway. An uncrewed Block 1B is planned to launch the Lunar Surface Asset in 2028, the first lunar outpost of the Artemis program. Block 2 development will most likely start in the late 2020s, after NASA is regularly visiting the lunar surface and shifts focus towards Mars.