Apostille vs. Embassy legalisation for Chad
Chad has not joined the Hague Apostille Convention, so a single British certificate does not finish a paper used there. Documents bound that way need embassy or consular legalisation instead, which puts a second desk behind the first. No apostille issued in Glasgow for use in Chad closes the file alone, and the consular stage adds the act that does.
Chad's Hague status & what it means
Outside that treaty the file is read more than once, by desks that never speak to each other. Each one takes the bundle at face value and matches what it holds against what the previous mark says it holds. The name is the hinge of that match, which is why a small inconsistency does more damage here than on a one-stamp route.
The Glasgow → Chad route step by step
Glasgow Registration Office at 45 John Street, Glasgow G1 1JE prints certified extracts of Scottish civil entries, and the extract carries the name exactly as the register holds it. That printed form is the reference for everything afterwards. Take a photograph of it on the day it arrives, so the agreed spelling is to hand when other paperwork is filled in.
The FCDO Legalisation Office at PO Box 6255, Milton Keynes MK10 1XX then adds the British mark and posts the set back to whoever sent it. It works from the sheet in front of it and does not compare that sheet with anything else you own. An apostille from United Kingdom to Chad therefore preserves a mismatch rather than catching it.
Cost & timing for this route
The British charge is £45 / document by standard post, or £40 / document next-day where the sender is a registered business, met per document rather than per envelope, with an official charge at the consular stage on top. Both are spent again from scratch if a fresh extract has to be sent, which is what an unnoticed name mismatch eventually forces.
A five-minute check worth the whole run
Lay the extract beside anything else that will accompany it and read the names in both, letter by letter, aloud. Then do the same with dates and places. What you need for an apostille for Chad is agreement across the set, and this is the last moment when producing it costs nothing but five minutes of your morning.