Tier 2 PBS Dependent EXTENSION

[Gnanasekar]

Hi,

My situation: Initially entered as Work permit holder in 2007 then moved to Teir 2 ICT visa and was on that for 5 years. By end of 2012 I managed to get ILR.

In the mean time I got married in early 2012 and got Tier 2 ICT dependent visa for my spouse. She hasn't completed her 2 year qualifying period for ILR. Based on existing discussion I understand she can apply for PBS dependent extension for which I just need proof of fund. I don't wish to go the FLR(M) route as that will make her to go through the language proficiency exam.

Questions:
1) Is the fund requirement should be just £600 for the past 3 months or should be more as the bank statement will be mine. If at all it should show some funds for me as well ?
2) When I was filling up the form online and about to submit where it gave options of supporting document. Out of those I have an option for NHS registration document (Proof of address) dated no more than one month ago. I don't understand that bit as we have a NHS registration document dated early 2012.
3) Should there be any covering letter at all along with my application as I remember I did this the first time when I made her visa application outside UK.

Thanks in advance for sharing your expertise.

[Gnanasekar]

Could someone share a helpful response please.