I have an issue with my ILR apl which is explained below

I have got my 5 years completed onWP & tier 1 as

Got my WP entre clearence on 12th July 2006
Got my Tier 1 stamped on 12th June 2008 valid till 12th June 2011

I sent my tier 1 extension application on 19th April 2011 to Home office and got the acknowledgement letter dated 7th may from them ( i still have 35 days for my tier 1 expiry). I attended biometric scan on 19th May 2011.

When i received my Tier 1 extension biometric card from Home office the visa valid from date is mentioned as 17th June 2011 ( my tier 1 got expired on 12th june). I Dont know why they havent gave me visa from 12th june and put a 4 days gap.

I am going to apply my ILR next week now. Could you please help me with this issue ? what should i do and what should i mentioned in the form. What kind of explanation i can give for this ?? do i have to put a separate covering letter for this ??

Please help .. thanks in advance

Regards