How do I restore store after failed 1-click upgrade?

[drlava]

Hi, I'm getting a little desperate here.  I've made a backup of my store and have restored it from failed 1-click upgrade in the past.  This time after the update failed with the infamous and common "jqXHR:" error, I clicked away to check on something, and can't find how to get back to the page where I can click to restore the shop from the backup. Clicking '1-click update' just gives an error " Error: "install" directory is missing "  I can't find the backup restoration page elsewhere in the admin panel, but it must be there, right?  Surely the restoration process wouldn't rely on your browsers web cache of a page that's gone in order to work?  Help!! thank you.

-Background: Trying to upgrade from 1.5.6.0 as my host is forcing an update to PHP 7 which is not backward compatible with PHP 5.

[drlava]

OK, given the silence, it appears that restoring a backup DOES rely on your browser's web cache of a page that no longer exists after a failed upgrade.  This is terrible design and the page should contain a warning: CAUTION: DO NOT NAVIGATE AWAY FROM THIS PAGE IF YOU WISH TO RESTORE YOUR SHOP!

I now have 147 database backup files named :

auto-backupdb_000001_V1.5.6.0_20190304-221520-41b7435c.sql.bz2

auto-backupdb_000002_V1.5.6.0_20190304-221520-41b7435c.sql.bz2

etc.  Does anyone know how to use these to restore my db?

Edited May 7, 2019 by drlava (see edit history)

[drlava]

To close the loop in case others in the future are searching, I was able to restore from these backup files by:

Logging into my sql admin site, exporting the current database (just in case), then dropping all tables and importing tables from these sql.bz2 files in numeric order.  To speed it up, they can be decompressed and the .sql sequences inside merged/concatenated together (I merged 10 at a time).