Varsihi Tap (Varshi Tap / Varshitap) does not have one fixed English calendar date every year. It always starts on a tithi (lunar date):

• Start tithi: Falgun (Fagan) Krishna Ashtami

– i.e. 8th day of the dark half of the month of Falgun (Phalgun)

• End tithi (Parna): Vaishakh Shukla Tritiya

– 3rd day of the bright half of Vaishakh, celebrated as Akshaya Tritiya / Akha Teej

Because these are lunar dates, the exact English (Gregorian) date changes every year and can differ slightly by location and panchang.

To know the exact start date for this year in your place, you should check:

• A reliable Jain panchang/calendar, or
• Your local Jain sangh / upashray / temple announcements.

You can read a simple explanation of Varsi Tap here: