Embassy legalisation for use in China
This service does not apply to China. China takes a single-step certificate added in Britain, so a paper leaving Liverpool is finished once that certificate is on it. Anyone setting out to legalize documents for China stops at the British desk. There is no consular stage after it, no second fee at a mission and nothing further to arrange.
Where the extra stamp came from
Most people arrive here holding a list. A Chinese employer, a university office or an agency hands over a paperwork list, and older ones still name a consular stamp, because that is how the route once ran. The list is behind the times rather than wrong-headed. Consular legalization for China plays no part in the current route, and chasing it would cost you weeks.
The Liverpool end of the job
Only one British office matters here. The FCDO Legalisation Office adds the certificate, and it works by post from PO Box 6255, Milton Keynes MK10 1XX rather than over a counter. Where the paper is a birth, marriage or death record, Liverpool Register Office at St George's Hall, St George's Place, Liverpool L1 1JJ can issue a fresh certified copy, so the sheet you keep at home stays where it is.
Cost and timing
An official fee applies at the British desk, and it is charged for each sheet. Standard work takes 7–10 business days, with an express lane at 2–3. Since embassy attestation for China plays no part, that is the whole of the clock. No consular queue sits behind it and no second office adds a wait of its own.
What a China file usually is
These papers rarely travel alone. A work-permit set can run to a degree, a police record and sometimes a marriage entry, and every sheet takes the same short road. Because document legalization for China needs one desk rather than three, running the whole set at once is easy, and the papers all come back together.
What would change this is a decision by China, not by any British office. While the single-step certificate is taken, embassy legalization for China from Liverpool has nothing to add to a file, and no mission has a role in it. Put the effort into ordering the right version of the record and getting the names and dates on it to agree with your passport.