Answer

If you mean Ashtāhnika Parva, then there is no commonly accepted Jain scriptural tradition that says Ravan celebrated it.

Explanation

Ashtāhnika Parva is a sacred Jain observance connected with devotion, worship, and spiritual discipline. Ravan is known in Jain tradition as a powerful and learned figure, but he is not traditionally described as a follower who observed Ashtāhnika Parva.

Spiritual Understanding

In Jain Dharma, the important focus is not on royal fame or power, but on:

• devotion to the Tirthankars,
• right faith,
• self-discipline,
• and karmic purification.

So, unless a specific Jain text clearly states it, we should not assume Ravan celebrated such a parva.

Takeaway

Short answer: No clear Jain tradition says Ravan celebrated Ashtāhnika Parva. If you meant a different Jain festival, I can explain that too.