The change follows an update by the disability access card provider Nimbus, which is recognised by many attractions and events.
Nimbus has split its former “standing and queuing” card section into two separate symbols: “difficulty standing” (a physical need) and “difficulty with crowds” (often linked to neurodivergence or anxiety).
During half‑term, Merlin says new eligibility for the ride access pass is being trialled.
Those whose Nimbus card shows only the “difficulty with crowds” icon will be asked to visit guest services for personalised support instead.
The approach will be reviewed after February before the theme park opens fully in March.
Jonathan and Cheryl Willis contacted BBC Your Voice when they heard about the changes to the ride access pass for half-term.
They had tickets to go with their son Joshua, who has autism, but say there is no way he will be able to join the main queues.
“It’s his special place,” Cheryl said.
“He has a special interest in rollercoasters – he’s going to be absolutely devastated if he can’t go.”