options for rollback from 1.5.4 to 1.3.8a?

[tp1687]

Getting ready to update an older site from 1.3.8a to 1.5.4 - doing it in a subdomain set aside for testing.

As a failsafe, after testing and once the site goes live, if it's *then* determined there are errors deemed worthy of rolling back to 1.3.8a, is it possible to do that once new transactions have been entered into the live database? In other words, how will 1.3.8a react with a database that has been used for a 1.5.4 installation? Or would we need to restore the previous database, losing those transactions?

Not expecting this to come into play - simply trying to cover all my bases here. Thanks!

[DrByte]

You would need to rollback the database, because passwords are encrypted in a different format in the newer version.
And the older version might not properly handle some of the changes to various database tables.