Editing start date of a macro calendar calculation

[akaau]

Hi,
I have an macro in which the week 1 for 2021 starts on 28th Dec 2020. The week 1 for 2022 starts from 3rd Jan 2022, however in the macro i don't see an option to edit the start date.
Can someone please guide how can this be changed or what information is required from me for someone to analyse and confirm.

Thanks in advance.

[torachan]

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