firstly the ten years must be consequetive years and not as we like, in 80IA every business unit is looked as seperate one and no adjustments with other business carrried on by sse is allowed but once you come out of this section after 10 years you can very well claim unabsorbed depreciation loss set off agaist other business not eligible for 80IA provided the unabsorbed depreciation loss you suffer after you come out of section 80IA will only be allowed to be set off, and depreciation loss incurred while you are claiming 80IA will not be allowed to carried forward after you leave the said section