IR Replacements After Waivers Close:
IR replacements may remain on the roster and be sent down through the normal waiver system but can not be recalled as IR replacements after the waivers have closed. Two way contracts can still be called up as IR replacements as they don't use the waiver system to be called up or down. IR contracts for players signed through FA can be released or kept on the roster as normal but new free agents can not be signed after the free agency deadlines.
So after the waiver deadline only two way players can be used as IR players.
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