Query:- Deleting update package what will be impacted on old spec

Hi,

Today, I built and deployed the update package post that application is not working as we want some new code also promoted so if we reinstall the package and restore the old spec and again promote and do an update package build and deploy and test the issue.

I would like to perform below steps to retrieve the old spec on the server.

1.Deleting package which having issue from the server ( Package build)- reinstall.

if not

2.Restore the old spec and deploy.

Just deleting an update what will be losing? Which we deployed that package directory and that spec which those entry is going to me and old spec will be still to accessible to server. Is this correct my understanding or wrong? Kindly help on this.