quick questions about my application as I need to plan summer travels.
1)
I am on spouse route and need to do my FLR-M..
Visa sticker on passport 25/11 to 25/12 - 2019
I entered UK on spouse visa 21/12/2019
Dates on BRP 19/11/2019 to 25/8/2022
Which date should I use to apply. I heard about maximum 28-day transferability rule.
My understanding is that I can apply 30 months after entry and before BRP expiry, hence apply on or after 21/6/2022 and before 25/8/2022, is my understanding correct?
2)
Cohabitation documents
In the bank statement (joint account), it has my name and address (when I login with my credentials) and down where it says account name it has both of our names. When my spouse enters the credentials the statement has the spouse name and address and account name has both our names. I hope I am making sense

Does this count as one joint document (1 of 6) or I have to treat it a separate and include both (2 of 12)?
Same as the gas bill, company allows one name in the address, so it says "Mr. HUSBAND & others" and address, then down it says Dear Mr. HUSBAND and Mrs. WIFE. Do I count this is joint names?
3)
What is considered the application date? The day I submit the application OR the day I do my biometrics?
In other words if my understanding is correct above and I can only apply after 21/6, can. Submit the application earlier but schedule the biometrics after?
4)
I live in Liverpool but I have to spend the summer in Cardiff, can I do my bio in Cardiff or it has to the city where I reside?
Thanks