Police guy won't call you before hand. He literally comes to check if you're living in the place you mentioned in the documents. And he may ask your neighbors also to confirm that. You can go to police station, explain your predicament and since its due to baby boy, I'm sure the police will help you.
Just for reference, few years back when the guy came for verification, I was in a office with no signal. when I came out, I had like 5 missed calls. Called back and it was police guy. I explained him my situation and he said no problem, tomorrow I'll come, be in home. Next day I was in home, the guy came, collected his bribe and gave his green signal