Not sure why this issue is only affecting the select few (myself included), the weird thing was when the main release happened on the 18th of August the full package downloaded in a couple of hours.
I then made a minor mistake a couple of weeks ago in upgrading my main SDD but not backing up the MSFS files to save re-downloading them all again thinking it would only take a couple of hours BIG MISTAKE..
After installing the new drive went to download MSFS again and it kept getting stuck on certain files, I tried all the tips given out by the dev team none of it worked, kept looking on the main MSFS forum for a cure whilst pausing and resuming the download which worked to some degree.
Kept doing that whenever I wasn't at work and finally it finished the download around 4-5 days I left it running overnight and whilst I was at work (shouldn't of taken that long on a 350mbit connection though) WooHoo I thought THEN update 2 got released and it did it again with that looping thing.
I left it overnight and the next morning whilst I was at work, still not completed so headed to the main MSFS Forum and found a couple of suggestions
These were:
1 - Changing the Routers DNS
2 - Download Netlimiter 4 and set the up & down limit to 2MB/s for flightsimulator.exe
I was so fed up of waiting I did both AND it worked the update finished in about 30 minutes.
In my router settings I changed from Cloudflares 1.1.1.1 DNS to Google DNS Servers, I also stuck with the 2MB/s limit but it may need adjusting up or down for others.