I'd say the person most likely to return would be Alex. This will be the 3rd time BB has chnaged this season so that someone who got kicked out, because of a bad coupling, can stay in the game. Sharon got a raw deal with Jacob and then suddenly the Neil had to leave, then they see that Ryan is going to leave because of Allison so they change the game again to keep him around. Of the 6 houseguests that are out of the house, Alex is the one who deserves back in the most.
I think this is just BB realizing that couples was a terrible idea.
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