Your understanding of the pattern is right in principle, but the exact dates work a little differently.

For Varshi Tap / Varshitap, the traditional rule is:

• Start: Chaitra Shukla Ashtami
• End / Pārṇā: Vaishakh Shukla Tritiyā (Akshaya Tritiyā)

This is according to the Jain lunar calendar, not fixed Gregorian dates. Because:

• The Jain calendar is lunar (Vikram Samvat),
• And Adhik Māsa (extra month) can come,

the full Varshi Tap for 2026–27 will indeed be longer than 12 months (around 14+ months in this cycle), but the anchor points remain Chaitra Shukla Ashtami to Vaishakh Shukla Tritiyā.

So:

• 11 March 2026 is a correct start day being used by many sanghs for the 2026 Varshi Tap sankalp.
• Alternate Ekāsan (fasting) and eating is a common Varshi Tap niyam, and that part of your statement is correct.
• The end will fall on Akshaya Tritiyā of 2027, but the Gregorian date (day/month of 2027) should always be confirmed from a reliable Jain panchāng for your location, because it varies slightly by desh / time zone.

For a simple Jain explanation of when to start Varshi Tap 2026 based on Chaitra Shukla Ashtami and Vaishakh Shukla Tritiyā, you can read more here: