The progress so far

I arrived in UK in 5 September 1997
Graduated from full-time university course 1 July 2003
Started work August 2003
Short period of no work December 2004 - January 2005
Restarted work February 2005

In August 2007 I apply for settlement under the Long Residence category

I receive a negative reply 6 weeks later because the home office was not satisfied that I had stayed in the country continuously legally in the past 10 years, after spending £750 for my settlement fee, and NO right of appeal.

I checked the immigration rules -- 

www.bia.homeoffice.gov.uk/lawandpolicy/immigrationrules/part7

which now clearly states
a) "continuous residence" means residence in the United Kingdom for an unbroken period, and for these purposes a period shall not be considered to have been broken where an applicant is absent from the United Kingdom for a period of 6 months or less at any one time, provided that the applicant in question has existing limited leave to enter or remain upon their departure and return, but shall be considered to have been broken if the applicant:

(emphasis mine)

which I was surprised about, because I had never seen it before.

A relative informs me of this new rule.

I cannot find a consultation document which explains this new rule.

I will seek legal advice on the basis that this change is unfair, has been done retrospectively, and there is no provision for me to prepare my visa status for this change, which could have eased my application.