Quarterback Geno Smith made it four years with the Jets. He may not make it six months with the Giants.
Unless the Giants plan to keep four quarterbacks on the active roster (which is highly unlikely), either Johnson or Smith will be gone, since it would be a major shock to see them give up on Webb so quickly.
Moving on from Smith would cost $300,000, with up to $100,000 of it being potentially recouped if Smith would sign elsewhere. Cutting Johnson would entail letting him walk away with a $100,000 roster bonus.
Elsewhere on the initial depth chart, the Giants list three starting receivers (OBJ, Sterling Shephard, Brandon Marshall) and no starting rookies, including first-round tight end Evan Engram, who is behind Rhett Ellison.