Lost loss

My client is an IT consultant trading through a limited company. He is confident that he is outside the scope of IR35 and I am willing to accept his assurance.
In a recent accounting year he did no work and so the company's turnover was nil. He continued to draw very modest salaries for himself and his wife and — with a few other recurring expenses — a loss was realised in the company's accounts. In the subsequent year he returned to work and the company was liable to corporation tax on the resulting profit. However to date I have chosen not to make a claim for the loss brought forward because I do not consider that it resulted from a trade being carried on and there was no reasonable expectation of gain during the year in which the client chose not to work. I am not aware...