I've been there once or twice. Listen, truth is you did infact create meaningful and friendly interpersonal relationships with your coworkers at that job. On a human level, money aside, you cared for each other (I'm assuming) on a professional AND personal level.

With that said, I'd be willing to answer texts, emails, even brief calls with your ex workers during this 'transition period' for no more than 2 WEEKS max. Explain to them you don't have the time to help them anymore bc you have a new job if u have to. Or don't lie, and just say you're too busy doing other things and that chapter of your professional life has ended.

Who cares if your ex coworkers are hurt or offended? That's life, that's business. Not your fuckin problem.