Good old reliable Pearce had also said he was likely to leave today not even hours before this news.
Just because Phillips signed an extension doesn't necessarily mean that Pearce was wrong about the likelihood of him leaving.
It seems to me that the club were trying to find a permanent move for him to cash in after he had a good season, but in the absence of any takers at a reasonable transfer fee they decided to be prudent and sign an extension to retain his sell-on value with a future sale in mind.
There will surely be some PL teams in need of a CB in January (there always is), and with an extension in place LFC can get full value rather than having to settle for a cheaper deal due to him having less than 18 months remaining on his deal.
This approach has served the club well in maximizing profits for fringe players like Solanke, Brad Smith, Ibe, etc, though there is admittedly also some risk involved in the event that a players value could decrease and the club getting stuck with a contract, like what happened with Karius, Mignolet, and is happening now with Origi to a certain extent.
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