Yes satan has access to Gods throne for the purpose of accusing the brethren,. he is the prince of the air at this time .
Actually that was satan fall from grace , satan formerly was known as Lucifer , the most powerful - most beautiful Cherub angel God made.
He was the annoited cherub a very special cherub .
Lucifer because he became conceited with pride boasting that he will be like the Most High , his high ranking status was being supreme being in the Garden of God and he sinned against the Most High God.
Then God cast Lucifer out of the Garden of God , this was before Adam was created . The result of Lucifer sinning against God was God casting him out of the Garden of God losing all status as a anointed cherub.
Jesus was speaking of how fast Lucifer lost it all , as fast as lightning he fell from the highest anointed cherub to the enemy of God
There is no redemption for angels and lucifer became known as ha~satan as he became very angry that God created Adam to rule in the Garden after it became filled with vegetation -so lucifer became Ha~satan after mankind took his place in the Garden and has sought to and still seeks to cause God's beloved humankind to turn against their creator.,
He is still at it today accusing people of their sins
lucifer fell from the highest anointed cherub and out of the 3rd heaven as fast as lightning , though now he is called the prince of darkness , the prince of the air and he will soon be cast down to earth when the Man of Lawlessness appears on the world scene , it is one of the woes in the Revelation ,
if you need scriptures I can get them later