when to preform qadha salaah

I begin in the name of ALLAH TAALA and peace and blessings on the best of creations Nabi(saw).
Assalaamu Alaiikum Wa Rahmatullahi Wa Barakatuhu
Respected Mufti
Can Qadha salaat be performed between asr and magrib or after fajr.I understood it to be makrooh times, but heard recently that qadha-e =-umri may be performed at these times.I also heard that if a person does not have a single qadha in their lifetime it would be right to perform for example Asr at the time of sunset just before Esha.Also I was informed that if I had for example Zohr qadha and it is Asr time,I could perform my Zohr qadha before performing myAsr Salaat.
Jazakallahu Khairan