Thanks for the error detail — that 422 “extra_forbidden” on

schedules[0].replaces

means the API model that validates deployments does not allow a

replaces

field under

schedules

for the version you’re running. What’s happening - In Prefect 3.4.7, the deployment schema forbids unknown fields (Pydantic extra="forbid"). A

replaces

key in a schedule object is not recognized there, so the request is rejected. - Your payload appears to include

replaces: null

(the error shows

input: None

). Even if you don’t intend to use it, sending that key at all will trigger the “extra inputs are not permitted” error on that version. How to fix - Remove the

replaces

key from each schedule you send when creating/applying the deployment. Also ensure your config generator doesn’t emit

replaces: null

. - If you were trying to rename/replace an existing schedule slug: - On Prefect 3.4.7, you’ll need to handle it by removing the old schedule and adding a new one (i.e., update the deployment so the old schedule is omitted and a new schedule with the desired slug is included), rather than using a

replaces

field. - Alternatively, upgrade Prefect on both client and server to a version that supports schedule replacement semantics and keep them in sync. A client/server version mismatch can also surface as schema validation errors. If you can share how you’re applying the deployment (code snippet or the relevant part of your `prefect.yaml`/JSON body), I can point to the exact field to remove and suggest the safest way to update/rename your schedules without leaving stale ones behind.