No firm fed offer until appropriations pass?

[Anonymous]

For those with fed hiring experience -- is it typical that a final, hard copy offer is held off until a department's appropriations bill passes?

My wife was offered a job -- salary negotiated, etc., all over email -- but the manager won't send the final, hard copy of the offer via snail mail until the appropriations bill passes.

Is this typical? Maybe it depends on the fed department?