It is always good to have a management plan that takes climate change into account.
However, in the case of mackerel and similar species, the variation in conditions from year to year is very difficult to predict.
Currently, the climate is tending to warm up, but there will still be years that are colder than others. These colder years will probably favour a better temporal overlap between larvae and their prey. You have to be patient and, above all, you have to leave breeders in the environment. Then, when these conditions are met, there will be sufficient egg-laying to support a large cohort.