error during Bamboo version downgrade

[PRASHANT GANJI]

Hey Team,
Recently we upgraded bamboo server from 8.2.7 to 9.2.6 for testing and now that testings are over and trying to rollback the version to 8.2.7 again I am getting bootstrap error as builds are not matching.
Updated bamboo.cfg.xml following the build numbers but that is throwing 404 error and currently bamboo server is not accessible 
need some inputs on this

[Eduardo Alvarenga]

The <bamboo-home> folder needs to match the DB version. Unfortunately using different DB and home versions will not work.

For the <bamboo-install> content, you can copy from a Bamboo installer and only make the adjustments to its:

• conf/server.xml
• bin/setenv.sh (Linux)
• bin/setenv.bat (Windows)
• atlassian-bamboo/WEB-INF/classes/bamboo-init.properties

Best regards,

Eduardo Alvarenga
Atlassian Support APAC

--please don't forget to Accept the answer if the reply is helpful-- 

[Eduardo Alvarenga]

Hello @PRASHANT GANJI 

Downgrading to earlier versions of Bamboo is not supported due to the many changes that happen in the product structure and database between releases. The only supported downgrade path is restoring your <bamboo-install>, <bamboo-home> and Database from a snapshot or file level backup.

Best regards,

Eduardo Alvarenga
Atlassian Support APAC

--please don't forget to Accept the answer if the reply is helpful-- 

[PRASHANT GANJI]

Thanks @Eduardo Alvarenga 
I had a backup of bamboo-home directory, but don't have snapshot of the volume attached..
is there any work around