Dev Uthni Gyaras (Dev Uthani Gyara) is a Jain festival observed on Kartik Shukla Ekadashi (the 11th day of the bright half of Kartik). It marks the time when gods are believed to wake up from their Chaturmas rest and return to their duties. In Jain communities, this day signifies the reopening of temples and the start of regular religious and social activities after the monsoon-period Chaturmas. Rituals often include puja and ceremonies that mark the beginning of new cycles of worship and community events; many families also begin auspicious preparations and devotional programs around this time. The exact rituals can vary slightly between Digambara and Śvetāmbara traditions, but both groups commemorate the same idea of divine awakening and the resumption of daily religious life. Dates shift each year according to the lunar calendar.

If you’d like, I can point you to a Jain Knowledge page that covers this festival in more detail.