This section applies where under section 257 the debtor's creditors are asked to decide whether to approve the proposed voluntary arrangement.
The creditors may approve the proposed voluntary arrangement with or without modifications, but shall not approve it with modifications unless the debtor consents to each modification.
The creditors shall not approve any proposal or modification which affects the right of a secured creditor of the debtor to enforce his security, except with the concurrence of the creditor concerned.
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In this section "preferential debt" , "ordinary preferential debt" and "secondary preferential debt" each has the meaning given by section 386 in Part XII; and "preferential creditor" is to be construed accordingly.