ILR- 180 days absence - summarised understanding and Query

Hello,

I have gone through lot of posts here and FAQ section ( http://www.immigrationboards.com/viewtopic.php?t=79378 ) especially Question 17a, 16 and Q3. I have few questions and for the sake of clarity , I am citing my wife's case below:

Visa granted : 05-Feb-2009. Arrived UK: 26-march-2009 Absence : 49 days.
leave --> 2 july 2009 to 12 september 2009 Absence: = 70 days
leave --> 8 oct 2010 - 6 nov 2010 Absence: 27 days
Leave -->5th nov 2011 - 11 dec 2011 Absence: 34 days
Visa renewal in Feb 2012. New expiry date : 23 Feb-2014.
Leave -->5 jan 2013 --7 feb 2013. Absence: 31 days

total absence: 211 days ( inclusive of late arrival absence of 49 days ).
total absence: around 160 days excluding late arrival absence.

Here are my questions:
a) I have heard and read a lot about 180 days absence rule. is it true that 180 days is applicable ( for tier-general ) in any one year and doesn't cover whole of 5 years. put differently, In my wife's case she hasn't stayed out of UK for more than 180 days in any 12 consecutive months but overall she has stayed for 211 days abroad in a five year period.

b) if 90 days concession is applied, which will mean that her clock for ILR started on 5th of feb 2009 then will her late arrival by 49 days be considered in the absence calculation ?? I know Q17 clearly answers but I am seeking confirmation.

c) Today is 4th of Jan so does it mean that my wife becomes elligible for ILR from around 8th of Jan 2014 onwards...

NOTE: few of members here may find my post bit irritating as I am simply repeating information already present here but what I am trying to do it to assimilate staggered piece of information with the help of my wife's example.

I assume your spouse is a qualifying PBS applicant. So far as absences are <180 days per 12 month period should be ok. Apply from 28 days before 05-Feb-2014.

Thanks for your reply.