This is not my understanding (as confirmed by to me by the office of the Ombudsman).
For long term products, you can make a complaint to the Ombudsman within any of the following limits:
- 6 years from the date of the conduct concerned
- 3 years from the date on which you became aware, or ought reasonably to have become aware, of the conduct concerned
- Where it appears to the Ombudsman that there are reasonable grounds for a longer period and that it would be just and equitable in the circumstances to extend the time limit