Start-up Costs - Employer Contribution Credit - Cash or accrual based employer contributions

Are the contribution that qualify for the employer contribution portion of the Start-up contribution tax credit based on:

1. Contributions actually made during the tax year you are taking the credit for (2023 credit uses only eligible employer contribution actually paid prior to 12/31/2023)

2. Contributions applicable to the 2023 regardless of when they are paid. (Inclusion of contribution for 2023 that are either paid in 2023 or as a receivable payment in 2024)

The draft instructions for form 8881 which were just released this month would not seem to be clear.  The instructions use the language "made by an eligible employer for the first tax year during which the plan becomes effective with respect to the eligible employer and the succeeding 4 tax years."