Short answer: No, in Jain scriptures there isn’t a day described where 300 Bhagwan (including those of previous chovisiś) all gain kalyanak on the same day and where paap and punya are multiplied.

What is described in Jain Dharma:

• Kalyanak is the birth/renunciation/complete enlightenment event of a Tirthankara. Each Tirthankara (out of the 24) has their own kalyanak at a specific time in cosmic history.
• There isn’t a concept of a universal day where many Tirthankaras simultaneously have kalyanak.
• Punya (merit) and paap (demerit) are karmic binds that accumulate over actions. Jain teachings describe the accumulation and reduction of karma through conduct, penance, and right knowledge, but they do not describe a single day where punya and paap are “multiplied.”

If you’d like, I can point to specific Jain texts that discuss the 24 Tirthankaras and how karma binds work, and I can include careful notes on any differences between Digambara and Śvetāmbara interpretations. For reference, you can explore related material here: