If your client overestimated an R&D Tax Credit spend know this:
Businesses may overestimate how much of their cost is linked to R&D, they might call an activity R&D internally but it might not meet HMRC’s guidance. With new product development, for example, the new product itself might not necessarily be innovative so to establish whether R&D had taken place we would focus on the steps taken to achieve the new product, successes, and failures. This is where the qualifying activity could lie.

If you have taken a figure for R&D qualifying activity at face value then you may struggle to justify the claim during enquiry.
Need help? Contact Eric Larson at: www.taxconnections.com/Eric-Larson/12275762/United-States/profilepage