Tax treaty termination: notice procedure and effect on subsequent taxable years with differing effective dates for income and capital. Article 31 provides a termination mechanism requiring written diplomatic notice after an initial five-year period, deliverable on or before the thirtieth day of June of a calendar year. The Convention ceases in Spain for taxes chargeable for any taxable year beginning on or after the first day of January of the calendar year following the notice. In India it ceases in respect of income arising in taxable years beginning on or after the first day of April of that calendar year and in respect of capital held on the last day of any taxable year beginning on or after that April date.