Where does it say, if you have an election to not pay CPP on self employed earnings and you have salaried income in the same year, your election to not pay CPP is voided?

An employee who wants to elect to stop contributing to the CPP will have to complete Parts A, B, and C of Form CPT30 and give a copy of the election form to you and any current and future employer. In addition, the employee will have to send the original election form to the CRA using the address shown on the back of the form. For instructions for employees, go to Canada Pension Plan (CPP) contributions for CPP working beneficiaries.

 If you are at least 65 years of age but under 70, you can elect to stop contributing to the CPP or revoke a prior-year election. For more information, see Form CPT30, Election to Stop Contributing to the Canada Pension Plan, or Revocation of a Prior Election, and Schedule 8 or Form RC381, whichever applies.

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