I'm not totally sure about this, but i think you'll need the information on page 38 of the Command Reference: http://ww1.microchip.com/downloads/en/DeviceDoc/40001784B.pdf
2.5.1 radio rx <rxWindowSize>
If you set it to 0, the device will be in Continuous Reception mode untill a packet has been received.
I'll look into it more the coming two weeks, but still got other stuff to do 