CRA generally will accept a late eligible dividend designation for an excess capital dividend amount election made within three years

S. 89(14.1) gives CRA the discretion to accept an eligible dividend designation that is up to three years late.  CRA generally will accept a late designation if the reason for the lateness was an honest and non-negligent mistake in calculating the capital dividend account at the time of making a capital dividend election, so that the taxable dividend arises as a result of a s. 184(3) election to deem the excess portion the capital dividend to be a separate taxable dividend.

Neal Armstrong.  Summary of 2 August 2013 T.I. 2013-0475261E5 ("Eligible Dividend - Late Filing 89(14.1) & 184(3)") under s. 89(14.1).