Having then appointed Allardyce in place of Koeman, Watford felt they received assurances that the Toffees would not pursue their former boss as a summer target, and if Silva is to be named as the next manager then Watford are reportedly prepared to explore their options.
Allardyce has been heavily criticised by fans for his management and Everton's style of play since he took over and the club said the decision was part of their "longer-term plan".
Ahead of the meeting, Allardyce has hit out at a lack of "decency" after Everton pushed ahead with boardroom changes by appointing Professor Denise Barrett-Baxendale to replace Robert Elstone as CEO with Dr Keith Harris becoming deputy chairman without his knowledge. Sam was brought in at a challenging time last season to provide us with some stability and we are grateful to him for doing that. "Generally there's no smoke without fire".
Allardyce, whose previous clubs include Bolton, Newcastle, Sunderland and Crystal Palace, landed his dream job with England in 2016 but that turned sour after only one match, with Allardyce stepping down following a newspaper sting.
But after Everton finished the season in 8th, the club opted for a change of direction.
Watford are still understandably irked by Everton's attempts to unsettle Silva over a two-month period during his preliminary stages at Vicarage Road, with reported offers of up to £12 million, in an attempt to hijack his services early.
Asked about the situation, Allardyce hit out at the club.