As I live in India, and as you may be aware India has always been a spiritual country since more than 5000 BC, we have the Himalayas on the North and several sages are in a state of deep meditation here. My Guru or Master, spent 16 years in the Himalayas before coming back to society to give to the masses free of cost what he received. He was bestowed with various blessings by more than 11 sages and spiritual masters to go and distribute the knowledge of meditation and kundalini awakening to the general public. That is what he is doing since 1999.
The energy levels between 3.30–5.3am are high because the Masters are in a state of deep meditation, continuously sending messages at higher frequencies to those who can connect. Secondly, at this time everyone is asleep and there is minimal thought pollution, whose energy can disturb your meditative practice.