They have watched the show, so know Mark is the favorite, the most obvious winner and this will be the only realistic chance to get rid of him, and by virtue shake the game up and create unpredictability, otherwise we will sleepwalk to a Mark victory.
If Mark goes, everyone else's chances improve by 100% and Winston will be a beatable favourite, even female version of Mark Zoe could win as a newbie and get his votes. There's £100k up for grabs, so should not feel bad about evicting him as he's got £5k already. Sadly the 3 newbies aren't strategic, they are going to pick those who they don't like [HMs who would go anyway] and the producers have carefully picked 3 who like him.
Ash,
The newbies should evict him, to open up the game
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