Class A exemption applies
[i:868fb2d4d6] (1) a dwelling which satisfies the requirement set out in paragraph (2) unless it has been such a dwelling for a continuous period of twelve months or more ending immediately before the day in question;
(2) the requirement referred to in paragraph (1) is that the dwelling is vacant and –
(a) requires or is undergoing major repair work to render it habitable, or
(b) is undergoing structural alteration, or
(c) has undergone major repair work to render it habitable, if less than six months have elapsed since the date on which the work was substantially completed and the dwelling has continuously remained vacant since that date, or
(d) has undergone structural alteration, if less than six months have elapsed since the date on which the alteration was substantially completed and the dwelling has continuously remained vacant since that date;[/i:868fb2d4d6]
The property in question is undergoing structural alteration and has been for less than 12 months so it falls under 2(b).
Once the alterations are substantially complete the dwelling falls under 2(d).
The fact that the dwelling has previously been exempt class C is a red herring. Para 1 limits [b:868fb2d4d6]this[/b:868fb2d4d6] exemption where the dwelling falls into one of the criteria in para 2 and has done so for 12 months. Prior to the alterations starting it did not fall into para 2.
You should award the class A exemption from the date that structural alterations began and end it either 6 months after work was substantially completed or on 18 April 2006, whichever is the earlier date.
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