Interesting tidbit, there was a bug in the computer assisted part of the proof (now fixed):

"Many thanks to Brendan McKay and Gordon Royle for letting me know overnight that they had successfully 4-coloured my 1567er; as a result I found a bug in the part of my code that implements the relaxation described in section 5.4 and now it agrees. "

Source: https://gilkalai.wordpress.com/2018/04/10/aubrey-de-grey-the...