Alright, correspondence time!
So I've dug out from the biscuits archives the following original documents which should hopefully cover all the bases, and hopefully at the right times. There's definitely too many here, but this is the shortlist. For reference, the visa expires early February, and our appointment is mid January.
a) Bank statement, 01/11/2015-30/11/2015, in both names (applicant's maiden name shown on bill)
b) Bank statement, 01/03/2016-31/03/2016, in both names
c) Bank statement, 01/03/2016-31/03/2016, in applicant's name
d) Council tax bill issued 18/03/2016, in both names
e) Bank statement, 01/07/2016-31/07/2016, in applicant's name
f) Bank statement, 01/07/2016-31/07/2016, in both names
g) Credit card statement, 22/07/2016, in sponsor's name
h) Electricity bill issued 26/10/2016, in both names (applicant's maiden name shown on bill)
i) Gas bill dated 26/10/2016, in both names
j) Bank statement, 01/11/2016-30/11/2016, in both names
k) Bank statement, 01/11/2016-30/11/2016, in applicant's name
l) Council tax bill dated 17/03/2017, in both names
m) Credit card statement, 23/03/2017, in sponsor's name
n) Bank statement, 01/03/2017-31/03/2017, in both names
o) Bank statement, 01/03/2017-31/03/2017, in applicant's name
p) Broadband bill dated 31/07/2017, in both names
q) Water bill dated 07/08/2017, in both names
r) Electricity bill dated 25/10/2017, in both names
s) Broadband bill dated 29/11/2017, in both names
t) Bank statement, 01/11/2017-30/11/2017, in applicant's name
u) Bank statement, 01/11/2017-30/11/2017, in both names
So, question is, which should I keep and which should I take out? Billing by the utility companies is irritatingly done at 6 month intervals, so only one will "do" per year. These are just about misaligned with the council tax bills - council tax bills are March, gas/electric in October. To this end, I've put bank statements in which will map to November, and similarly around July, which should make up the 4 month spacing (March - July - November). These are separate bank statements to those being used for the financial evidence.
The joint bank statements are pretty weak for those particular months (having usually just one transaction on) - does this matter? (I guess not, but it "feels" weak).
I also have statements from our broadband company, Virgin, but these aren't strictly phone bills, as we're broadband only. Are these good or not?
I'll be taking a bonus bag along to our in-person appointment with all of the other documents we have so I can always pull another one out if it doesn't suffice on the day!