I have found his conviction.
22 March 2019
// Khairi Saadallah, 24, of Coronation Square, Reading. Common assault of an emergency worker. Imprisoned for two months consecutive. //
So in March 2019 he had a knife when he attacked the emergency worker, went to prison, came out in July and was arrested in August for attacking the Sainsburys guard and tied to stab him with a broken bottle.
I suspect he may have a drink problem.