[quote="heexists"]I had been granted HSMP visa on September 10 2008 and first entered the UK on October 07 2008. So calculating my earliest appointment date I am getting September 09 2013. Am i correct?[/quote]
No, you can apply up to 28 days before September 10 2008 according to this:
http://www.ukba.homeoffice.gov.uk/sitec ... iew=Binary
The period between entry clearance being issued and the applicant entering the UK may be counted toward the qualifying period, as long as it does not exceed 90 days. This can occur if the applicant is delayed travelling to the UK. Provided the period of delay does not exceed 90 days, it will not be counted as an absence.
Or this:
https://www.whatdotheyknow.com/request/ ... ponse.html
Q. If I delayed my entry to the UK by less than 90 days, can I still apply at a PEO 28 days before my leave expires?
A. Yes you can still make your application at a PEO 28 days before your current leave expires