https://bleacherreport.com/articles/10113608-stefon-diggs-rumors-belief-bills-will-rework-contract-avoid-trade-in-free-agency
"If they were to get rid of Stefon Diggs, if they couldn't rework his contract, it would require a trade. But there's also a belief that they can get to a place with Diggs that they can get a restructured contract to still keep him in Buffalo and still keep him happy. As we know, though, last offseason this got a little bit sticky. We'll see if general manager Brandon Beane, one of the best in the league, can keep this situation peaceful and keep Stefon Diggs on the roster this coming season."
Per Spotrac, a pre-June 1 release would result in $49.5 million in dead cap and a pre-June 1 trade would give them a dead cap hit of $31 million.
A post-June 1 release would yield a dead cap hit of $27.3 million this year and $22.2 million next year, whereas a post-June 1 trade would result in $8.8 million in dead cap and $19 million in cap savings this year, but also a $22.2 million dead cap hit next year.
If the Bills intend to keep their No. 1 wide receiver and pair him with free-agent signing Curtis Samuel, as well as a potential early draft pick, they have a couple options to make his contract more palatable.