Re: They want to delay as long as possible ...
The essence of limited companies and especially of those listed on major stock exchanges is that the share ownership of widely distributed between those who play no part in the management of the company and share ownership is not limited to "powerful and rich people". In fact most of the ownership of PLCs is likely to distributed between pension funds and other investments. If you have any sort of pension fund including corporate pension funds and workplace pension schemes you will have a smidgeon of ownership of a lot of companies, possible even PO and Fujitsu. Does this make you a "rich and powerful person" and more to the point, if your pension scheme owns shares in these companies should you, personally, be prosecuted for their wrongdoings? A company might well be successfully sued for compensation or prosecuted for corporate wrongdoings but that, rightly, does not extend to those who, quite possibly unknowingly, hold shares in it.
Having said that there is no protection for individuals within a company if they knowingly and deliberately break the law in determining and following some course of action for their company. That would include any perjury in providing evidence,* any deliberate perversion of the course of justice or any conspiracy to do those things.
* I spent about 14 years in a job where providing evidence was the sole purpose. I was never in any doubt that the responsibility for the truth of that evidence was solely mine and not that of my employer.