Check block size on recreate #3758 was the fix five days later. Problem is that Beta is 13 months old. Hopefully this problem will be fixed soon. Stay tuned for an Experimental, which is sort of a pre-Beta.
What version are you on? If you’re willing to install the Canary release (which looks like it’s on its way towards the long-awaited Beta upgrade) on the system, it will possibly avoid a problem if you’re stuck around 70%-100% on the progress bar, and if About → Show log → Live → Information shows that dblock file downloads are constant. I think all downloads pass through the temp dir. The remote files typically are encrypted ZIP files, and some of the processing of opening them to look for blocks uses actual files on the drive. While you might have genuinely missing blocks, the odds seem good you hit:
Empty source file can make Recreate download all dblock files fruitlessly with huge delay #3747
If you mean something was there in 10 mins, and it didn’t change, and you assumed it was complete, what probably actually happened was it went into fruitless-search mode and had nothing more to add. Looking inside the DB with a DB browser would probably show a flag saying it’s still being worked on.
If you have another system, you could try installing Canary there and doing direct restore just to see if the partial temporary database recreate step runs well. You don’t need to actually finish restore unless you want to verify that all goes well if the original system is lost. Personally I’d recommend the current Canary for general use anyway (due to all the fixes), but downgrade to Beta is tough, and I don’t know whether you want to be extremely careful, have old versions you value highly, etc. Many options exist.
If you install Canary, you can consider changing Settings to Beta to stop a new Canary with new bugs. While they’ve been very good lately, they’re unpredictable because that’s where the new code goes in.
Releases can be checked to see if a given one comes with warnings, and what the feedback on it is…