When replacing the JD boot files, a 2% progress is shown.
check the 00_00 files of the different zip and none of them corresponds to 80% (approximately what I remember).

"size" : 71128698880,
"host" : "docs.google.com",
"enabled" : true,
"created" : 1568943370479,
"uid" : 1568943376797,
"urlProtection" : "UNSET",
"linkStatus" : null,
"current" : 1448684799,
"finalLinkState" : null,
"chunkProgress" : [ 1448332944 ],

The way would be for JD to analyze the file size again and how much is missing.