There will be departures from a squad where contractual clauses mean most players would take significant wage cuts, up to 50% in some instances, in the event of relegation, BBC Sport has been told.
Axel Diasi, Adama Traore and Callum Wilson are all out of contract in the summer.
Midfielder Mateus Fernandes has been linked with Paris St-Germain and Manchester United and seems certain to move on, with West Ham hoping for a significant profit on the £40m they paid for him last August.
Senegal defender El Hadji Malick Diouf cost £19m from Slavia Prague in July. He is also a player West Ham could make a profit on.
The problem is there are plenty of others West Ham will struggle to shift, given some calamitous recruitment since that famous night in Prague – the £105m subsequently received from Arsenal for Declan Rice, and more, has been squandered.
They paid £40m to sign Max Kilman from Wolves in 2024 on a seven-year contract. He hasn’t played a single minute since the end of January.
Germany striker Niclas Fullkrug signed a four-year deal in 2024, when he was 31. He joined AC Milan on loan in January after scoring just three goals in 29 appearances for the Hammers in an injury-troubled spell.
James Ward-Prowse still has another year left on the contract he signed in August 2023. He started seven games and was a substitute in another five after joining Burnley on loan in January.
The list goes on.
Next season, West Ham must face up to a challenge those fans who celebrated success in Prague could never have imagined possible.
A lot of work lies ahead if they are to make a success of it.
