In drafting transitional provisions, it's common to write the first clause that's concerned by the transitional provision in question as a benchmark clause in that transitional provision.
That specific provision in this case states that, if the act comes into force during the election period, the previous version of the act applies with respect to the election and all related obligations and rights, including obligations to report and rights to reimbursement of election expenses.
Section 299 was selected in accordance with this legislative drafting convention. It is the first section in the act that concerns candidates' obligations. However, the Chief Electoral Officer raised a concern about this section in one of the appearances he made before this committee after the bill was introduced.
"Section 299" has been replaced by "section 1" simply to express clearly that this transitional provision applies to all rights and obligations resulting from the act, particularly those with respect to third parties, candidates and registered parties, but also the other rights and obligations arising from the changes made by the bill.
For example, if the bill came into force during a by-election, none of these provisions would be in force for that by-election. The by-election would continue to be administered under the previous version of the Canada Elections Act.
This is a common transitional provision found in most bills amending the Canada Elections Act.