PPR problem?

Client purchased and lived in home 'A' for a year while working self-employed (he's not a builder).

Due to lack of work client then did some property improvements on home A to 'fill a year when I had little work on but had some savings and time to invest'.

Time goes on.

Client manages to get a loan to purchase property 'B'

Spent lots of time doing it up (as it was a wreck) before finally moving into it.

Lived in house A all the time until B was complete and habitable - then moved into house B and put house A on the market.

House A was purchased in March 2006 for £200,000.

House B was purchased in October 2008.

Client moved into House B early 2011.

House A marketed for sale from time house B was occupied. Never been rented out, still empty, on market at a reduced price of £300,000.

If there is a gain on house A (I don't know as I don't have all the figures), do I have a problem with PPR relief and CGT on house A or do we just have to write to HMRC explaining the situation and the timeline, as it's now over two years since the purchase of house B?

Or am I worrying un-necessarily?

Any comments gratefully received.