Under IFRS, changes in accounting policies are

a. Permitted if the change will result in a more reliable and more relevant presentation of the financial statements.

b. Permitted if the entity encounters new transactions, events, or conditions that are substantively different from existing or previous transactions.

c. Required for material transactions, if the entity had previously accounted for similar, though immaterial, transactions under an unacceptable accounting method.

d. Required if an alternate accounting policy gives rise to a material change in assets, liabilities, or the current year net income.