Akalbodhan is the worship of Devi Durga in the month of Ashwin which is an uncustomary time for commencement of the worship. It is called so since the period of the worship of Goddess Durga differs from the conventional period or during the spring season (Basanta).
Akalbodhan is also described in the 'Kritivaas' writing. During the war between Rama and Ravana, both were equally handled by each other. After sometime, Ravana is in prayer of Rama to get the victory of this battle which made Rama surprised. Rama's first and foremost duty was to protect or to save his disciple. After that moment, Rama suffered from indecision. By seeing these, all the gods and goddesses became sorrowful and started planning to inspire Rama to kill Ravana and finally it was decided that Devi Saraswati would be on the tongue of Ravana and she will make him to say some evil words so that Rama could continue with the battle. Rama started the battle but got frustrated again and he suffered a lot for his Sita. After that all the gods felt the pain of him and decided to celebrate a Durga Puja for the intention to kill Ravana.