Each mark signs for the one before it
The thing that surprises people about a chain route is what each desk is actually looking at. It is not your record. It is the mark that the previous desk left, and the question it answers is whether that mark is genuine. Every stage therefore depends on the one before it existing already, printed and joined to the sheet.
That single mechanism explains most of the rules that otherwise look arbitrary. It is why the sequence is fixed, why nothing can be run in parallel to save a week, and why the bundle must stay in one piece between stages. Pull the sheets apart and the next desk loses the very thing it was asked to look at.
Why this corridor uses a chain at all
Myanmar has not joined the Hague Apostille Convention, and that is the whole reason. The single-certificate route is a shortcut agreed between the countries inside one treaty, and where the treaty does not reach, the older chain is what remains. So document legalisation for Myanmar runs through more than one desk, in a set order, with consular legalisation closing it.
There is no apostille issued in Leicester for use in Myanmar that shortens this, and no premium version that collapses the stages into one. An apostille for Myanmar is a certificate for a different set of destinations, so paying for one here buys a mark that the later desks in this chain are not looking for.
What running it out of order looks like
Out of order rarely means disaster. It usually means a return journey. A desk presented with a sheet that lacks the previous mark has nothing to certify, so the paper comes back roughly as it went, and the days spent are the loss. That is what you need for an apostille for Myanmar to be understood as: not a single purchase, but a sequence where each step has a prerequisite.
The calendar is where it bites. Because no stage can start early, a wasted leg is not absorbed by the rest of the run — it is added to the end of it, along with the post in both directions. Planning that assumes overlap between the stages will always come out short, however carefully the dates are written down.
The first link sits in the city
The chain starts with a paper fit to travel. Leicester Registration Service, at 115 Charles Street, Leicester LE1 1FZ, prints certified copies of civil records held locally, and that copy is what should go into the run so the original stays with you. It is the one link nobody else can put in place on your behalf.
After it, the FCDO Legalisation Office at PO Box 6255, Milton Keynes MK10 1XX takes its turn by post, as a government office rather than one of ours, and lists £45 / document for standard post with £40 / document next-day for registered businesses. There is no apostille from United Kingdom to Myanmar waiting at the end of that stage; the consular desk is what closes this particular route.