> (2) MODIFICATION OF CURRENT CONTRACTS.—In order to
limit NASA’s termination liability costs and support critical
capabilities, the Administrator shall, to the extent practicable,
extend or modify existing vehicle development and associated
contracts necessary to meet the requirements in paragraph
(1), including contracts for ground testing of solid rocket motors,
if necessary, to ensure their availability for development of
the Space Launch System.
Which explains why NASA isn't necessarily getting engines from Blue Origin or other cheaper new comers for example. The senate law dictates that they should continue using existing contracts. Now, could a NASA administrator argue that they should drop Aerojet (as cited in the ars technica article)? Potentially, but Aerojet could possibly sue, claiming that NASA is in violation of the law.