On the 13th April 2022, in the UK, I successfully upgraded the SYNC software on my 2016 Ford Fiesta 1.0 litre EcoBoost.  I did this by going on the Ford website:

https://www.ford.co.uk/owner/resources-and-support/sync-bluetooth/update#/

entering my Fiesta VIN number and then downloading the following file:

SYNC1.1_12345678_Update.zip                 (the numbers were not actually 12345678)

The size of the file was approximately 680 Mb.

Using the Windows Operating System, I then formatted a 1 GByte USB stick to FAT32 format, extracted the 9 files of which 7 were in the SyncMyRide folder (6 .cab files and 1 .sec file) then copied the SyncMyRide and autoinstall.lst and install.lst to the Root Directory of my USB stick.

I then downloaded and used the Ford 'SYNC_11_InstGuide.pdf' to give me the steps to successfully install the software update.

Several days earlier I attempted the process but went down various false routes.  One problem I came across was the Ford documents, I found online, did not have Release dates printed on them or Version dates so I had no idea how old or relevant these documents were.  Nor did they refer to which countries they were relevant in.  Some of the YouTube videos I watched said format the USB stick in exFAT format others in FAT32 format.

Ford Sync 1.1 - you’ll need a USB drive formatted as FAT32

If you search the forum you’ll see that there were some issues with the later firmware for 1.1 as hosted on the Ford servers. One of the members on here was hosting and providing a link to a functioning update. 

For me it only worked with exFAT, but from what I read on various clubs it seems that the quality of that stick also matters.... (sync 1)

Use the CyanLabs software, it's brilliant and the support there is second to none.

nice  mate..