From the transcript

These are areas that not only generally have lower densities, but they're also much more expensive to sample. And we've had constraint— financial constraints on the survey in the last few years, and those areas have been the ones that have been harder to include in the survey. And not only we have financial constraints, but we also have less interest from— the survey runs is undertaken by charter vessels. They need to post bids on the work, and if it's very expensive, like it will be with 4A, we're less likely to attract bids. And that has been the case in recent years as well.