It has been reported that NAC informed TPTB that he would not be renewing his contract when it's up in July. He offered to return to wrap up the story and finish out the contract and TPTB declined and released him early.
It's good that he was willing to honor his obligation but I also get TPTB declining it. Spencer "died" on 1/31/24 and has been offscreen since then. It would not make a lot of since to have him return for a few months, leave again, and then bring on a recast. This way, TPTB have ample time to find a recast and not only have coma as the reason they can throw in plastic surgery if they so desire. But going into the water, doesn't leave a lot of reasons that his face would require plastic surgery so I think it will just be a new actor. He will definitely have his work cut out for him because NAC put quite the stamp on Spencer as a young adult.