On Dashami, the final day of Durga Puja, the Sovabazar Rajbari has a tradition of releasing a pair of Neelkanth birds, symbolising Maa Durga’s journey back to Kailash. According to legend, these birds announce her return to her husband, Shiva. The Rajbari is known for immersing Maa Durga first, after which the rest of Kolkata follows suit. This immersion takes place at exactly 4:00 PM. However, due to the protected status of the Neelkanth birds, the practice of releasing them has been discontinued.
In 2018, Swapan Krishna Deb proposed replacing the birds with a phanush (a paper hot-air balloon). In collaboration with artist Prabir Krishna Deb, they crafted brightly painted phanushes featuring an image of a Neelkanth. The first is released from Sovabazar Rajbari, and the second from a boat on the Hooghly River, rising alongside the Durga idol as women in laal-paar sada saris and men in white panjabis and dhotis chant “Aschey Bochor, Abar Hobey" (Next year, it will happen again).