I suspect, although obviously we won't know until the off season for sure, that if EE and JB both walk Tulo will probably demand a trade out of here as well as was rumoured he did with Colorado.
Given that there is nothing on the FA market next year to replace them, the FO will then either have to replace EE/JB/Tulo via trade or start a full blown rebuild, unless they want to go back to the purgatory of 1996-2010 when we were not bad enough to tank and not good enough to get into the playoffs.