Scan and Connect iPhone to BLE sensor when the iOS device is in Background

Question

I want to connect to the BLE sensor every hour to my iOS device for transmission of data from the sensor to an iOS device. If the app is in foreground everything is fine from Discovery to Connection to Read/Write of data. After Reading/Writing to my BLE sensor, I disconnect the iOS device from the sensor and sensor goes to sleep.

Now when the next sync cycle comes (i.e. next hour) and the app is in the background I need to again scan for the peripheral and read data from it. Is it possible to give a command to scan for peripheral when the app is in the background?

1. I have enabled background modes as bluetooth-central.
2. I have implemented all delegates of CBCentralManager but did not get any callback when app is in background and peripheral is advertising data. (-didDiscoverPeripheral, or -didConnectPeripheral)

So my question is:

1. When my app is in the background where should I pass the command (scanForPeripheralsWithServices) by providing respective service UUIDs?
2. Is there a way by which I can scan BLE devices in the background continuously or on a certain schedule like every hour?