Principal calling current manager for reference

Hello everyone,

I finally have the required experience to apply for a school nursing position, so took the leap and applied back in August to a school district. Recently I had an interview with the Health Dept. and a principal at one school. I'm very interested in the position at this school, and was told that at the end of my interview that they were interviewing one more applicant, and the next step in the selection process would be to call references. Today I received a call from the principal verifying my current manager's phone number to call him for a reference. On the school district's website it says 'Notice: If you are selected for a job, your immediate supervisor will be contacted prior to a final offer of employment'. Do I take this to mean I should be getting an offer of employment if all goes well with them speaking to my current manager? It has me concerned that this will cause a rift in my department if they are called, I get no offer, and I continue to work there with them now knowing for sure I'm trying to leave. Has this happened to anyone else? Has anyone had their current manager called and not been offered employment? I'm just curious. I really hope to get a job offer, I've been wanting to be a school nurse since doing my immersion in nursing school. I'm nervous about the transition from hospital nursing but believe I am up for the challenge.

Any input would be appreciated. Thanks!