curl --request POST \
  --url https://api.hubapi.com/crm/extensions/cards-dev/2026-03/{appId}/views/migrate \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "allowDuplicateAppCardIds": true,
  "appCardId": 123,
  "legacyCrmCardId": 123,
  "helpdeskAppCardId": 123
}
'

{
  "message": "<string>",
  "endedAt": 123,
  "remainingPortalCount": 123,
  "startedAt": 123,
  "totalPortalCount": 123
}