OutofStateConcerned

I’m new to this so I hope it’s in the right spot but anyways I started a temp to hire position three months ago under the premise I was going to get hired while applying to PhD programs. Long story short, my employer is now saying that they may not actually hire anyone (everyone in my department is currently on the temp to hire track), but I’ve accepted an offer to a school out of state, far out of state. School is more than five months away. Should I tell my employer that I’m leaving now with the chance of never getting hired in the interim or wait until a month out so I can train my replacement under the assumption that they keep me on? Really could use advice. Thanks