Pybus's contract ran beyond the World Cup in England and Wales, but new Cricket West Indies (CWI) president Ricky Skerritt said changes were necessary and a "calculated strategic move" to reignite the passion for cricket in the region.
Barbados-born Reifer played six tests, eight one-day internationals and one Twenty20 for West Indies between 1997 and 2009 before moving into coaching.
"Up to the end of 2018 Floyd Reifer had been identified as the outstanding emerging local coach," Skerritt told a news conference in Antigua.
"He displayed this by leading the West Indies A team successfully, including victories against the England Lions, and ended the past year by coaching the Senior men's team to a T20 series win in Bangladesh."
England's Pybus replaced Australian Stuart Law in January. He guided the team to a test series win over England, while the ODI series against the top-ranked side ended 2-2.
Among other changes, Skerritt overhauled the selection panel, with Robert Haynes replacing Courtney Browne as interim head of selectors.
"We have found it necessary to immediately adjust our selection policy to become more open, inclusive, and player-centric," he said.
"I am therefore pleased to confirm that we have terminated the old embedded selection policy which secretly, but actively, victimised some players and banished them from selection consideration."
As part of the old selection policy, availability for domestic tournaments was a requirement to be picked for West Indies squads, but Skerritt said selectors would be allowed to pick all players who make themselves available.
Contractual disputes between players and CWI have weakened the team for several years, but Thursday's announcement could pave the way for players such as Keiron Pollard to return to the ODI fold for the first time since 2016.
"Participating in a World Cup is a career defining experience for West Indian players and coaching staff," Skerritt said.
"We therefore believe it is strategically more beneficial for a West Indian coach with the proven skill sets to have this exposure at CWI's expense - rather than a foreign coach."
Twice winners West Indies open their World Cup campaign against Pakistan in Nottingham on May 31.
First Published: April 12, 2019, 1:07 AM IST