There is an aspect of a spiritual sabbath released through the resurrection of Christ. I'm sure you already know this so no need to go into detail. Perhaps it is this spirital value that
@Hazelelponi is identifying rather than a physical day of the week which clearly is a static day and doesn't change.
How this pertains to law is a different matter. If we use circumcision as a heuristic then the spiritual is valued over the physical (in NT teaching). My question would be if circumcision, a sign of the everlasting covenant between God and Abraham for generations is spiritualized would it not be consistent the treat all law in the same way, especially another sign of a everlasting covenant?
How do we determine the physical for one everlasting covenant must be observed by the letter but another everlasting covenant may not keep the letter and keep it through spiritual means?
Of course this wouldn't replace the sabbath with another day which would be silly, but rather with released for all moments so we keep Christ over letters of stone.