From PM to Service Manager

As the title says, I have finally decided to move away from being a PM for a decade and accepted a Service Manager role and will start by 2nd week of April. The job requires project management understanding but that wouldn't be my core task. I have both PM and IT operations background and am PMP and ITIL Certified.

Is there anyone here who made a similar transition? I would appreciate it if you can offer any advice or tips. I would also like to know how was your first few months post PM life?