What is the ruling on what is known as "Haqq al-Laylah" (The Night's Due) on the night of the 15th of Sha'ban?

The night of mid-Sha'ban is a virtuous night, for the Prophet, peace and blessings be upon him, said: "Allah Almighty looks upon His creation on the night of mid-Sha'ban and forgives His servants, except for two: one who harbors enmity (mushahin), and a killer of a soul."

However, singling out its day or night for a specific act of worship is not supported by any evidence from the Quran or Sunnah; rather, it is an innovation (bid'ah).