After being in the UK since June 2018 I am ready to apply for FLR (M) in the coming weeks. The advice I received here last time was invaluable so I am back for round two 
Welcome back
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Not sure if you are aware, but everything is done online now and nothing is mailed anywhere... you complete and submit the online application, then you book a biometrics appointment at a UKVCAS centre, then before your appointment, you scan and upload all your documents to the UKVCAS website (including your passport and BRP)... or you can pay extra to have your documents scanned at the biometrics appointment.
A couple questions regarding the other options we have:
1. For Cat(A) is it okay to have a printed/stamped partial statement from the bank to confirm the December salary being paid in? We have all original mailed bank statements from 26th June - 27th November and are expecting 28th November - 27th December at the end of the month, but as he will be paid on the 30th December we would need a print out from the bank from 27th December through to the first week of January to catch the December pay. Hope that makes sense!
Yes, that's fine.
2. For Cat (D) with both the US & UK bank statements we would qualify now and would not need to wait until the end of December. My American bank statements are electronic only, have both of our names on it, but have my old address in the US on them (family still lives there) so I'm not sure if this would cause issues by having an address we don't reside at and non physical copies of statements. This is the last resort option we were looking at because we want to go as simple as possible...(I know, doesn't seem like it from my post!)
If the US statements are electronic, they must either be:
- stamped by a local US bank branch on EVERY PAGE,
or
- accompanied by a letter from the bank confirming their authenticity... which I assume you are not able to get done easily, given that it's a US bank and you are in the UK.
Therefore, I don't think it's a good idea to use this option.
Just going to rearrange your documents into the different upload sections for the application. Additions are in red
Applicant Documents1. Current US passport
(scan of every single page of each)2. Signed declarations and consent to checks forms (part of the online application)Proof of Identity/Travel History1. Current BRP
2. Husband’s passport copy
(scan of every single page)FinancesOption 1 - Cat (A) - Salary over £18600 for 6+ months •Letter from my husband's employer
a. Start date of employment (2012) and job title
b. Permanent, full-time employment
c. Current gross annual salary & salary before pay rise as it was within the 6 months (both over £18600)
d. Authenticity of P60 and payslips
•6 months’ payslips (Printed as received electronically and signed by my husband's production manager):
1. Payslip period 1st - 30th June 2020
2. Payslip period 1st - 31st July 2020
3. Payslip period 1st - 31st August 2020
4. Payslip period 1st - 30th September 2020
5. Payslip period 1st - 31st October 2020
6. Payslip period 1st - 30th November 2020
7. Payslip period 1st - 31st December 2020 (PENDING)
•Original corresponding bank statements received in the post:
1. Account statement dated 26th June 2020
2. Account statement dated 27th July 2020
3. Account statement dated 27th August 2020
4. Account statement dated 25th September
5. Account statement dated 27th October
6. Account statement dated 27th November
7. Account statement dated 27th December (PENDING)
8. Partial statement printed at bank to cover 27th December - First Week January (PENDING)
•Printed copy of eP60 for tax year to 5th April 2020
Option 2 - Cat (D) - UK savings over £62500 for 6+ months -6 months bank statements from 30 June - 31 December
- Declaration of source of savingsResidence in the UKAccommodation•Docusign signed tenancy agreement (printed)
•Original Council Tax Bill 2020/2021 (from Feb 2020 as it is billed in Feb annually)
Cohabitation1. Energy Bill (husband) & Water Bill (wife) dated December 2018
2. Water Bill (joint) dated April 2019
3. Cable (husband) & TV Licence (wife) dated August 2019
4. Energy Statement (husband) & Bank Statement of Fees (wife) dated December 2019
5. Water Bill (joint) dated April 2020
6. Pension (wife) & Credit Card (husband) dated August 2020
7. Notice from Landlord (joint) dated December 2020
Other•Original certified copy of Marriage Certificate
- Any previous US passports held since moving to the UK
- Any divorce decrees, if applicable
If you have any children in the UK:
- each child's passport
- each child's birth certificate
- a letter dated in the last 3 months confirming each child's address