Naturalisation - passport expires in march

I applied (on 25th January 2021) for Naturalisation application for myself, wife and 10 year old non-uk born daughter (All ILR +1 year).
I am worried: Daughters India passport is going to expire on 1st week of March 2021.

I have submitted application with current valid passport details however its naturally expire in second week of march 2021.
I tried to find appointment in near Manchester not getting any. earliest getting is on 22nd Feb but than have to pay 450+ GBP as 3 applicants.

If someone can guide please, (Sorry if this question answered here advance)
1. what Date they consider for Naturalisation application? I mean the date which most considered for processing of application.
Online Form submission ?
OR Biometric appointment ?
OR When Case worked pick up the case ? (I dont think this is but if case worker actually work on my application after 1 month, by the time passport will be expired)

Appreciate your help. (as always)

1. Date you submit and pay online is the application date. Application starts being processed and considered once biomterics are enrolled and electronic documents submitted to uvis by ukcvas.

Passports need to be valid on date of application and ideally, on the biometric appointment date.

Many thanks CR001. You comments helped me lot to understand the dates.
I was worried I will not be getting appointment by first Week of March, Luckily I found UKVCAS appointment on 22nd Feb in Manchester and booked.

Sharing my experience regarding booking appointment, if it helps someone.
Try at Mid night as slots opens. Also noticed slots open in morning between 8:45 to 9:00. They dont open all slots together, dont know how it work but night time seen only Paid slots opened. In morning seen mix of both opened.
It come and goes quickly and depends paid and free appointments. Keep trying.