What is the effect of explicit stipulations by the heirs regarding the approval and rejection of the bequests?

Primary text

If the heirs explicitly state, 'We approve one-third for you both and reject what exceeds it in your bequests,' or 'We reject half of each of your bequests and confirm the other half,' this confirms the division of one-sixth for each beneficiary, as it explicitly confirms the division of the excess portion.