The House of Lords has published a transcript of the oral evidence given to it by the Competition and Markets Authority here http://data.parliament.uk/writtenevidence/committeeevidence.svc/evidencedocument/eu-internal-market-subcommittee/brexit-competition/oral/70457.pdf
State aid is raised at Question 8.
In summary, the CMA states that it has no position on whether it should take on State aid responsibilities after Brexit, but sees that the “job might have its name on it”. It further notes that it would be likely to need to recruit State aid expertise at official and panel level, but is confident of its ability to do so.
George Peretz QC