I've maintained link integrity for a long time on my personal site using a similar tactic, however for me anyhow the new Wordpress version of the site had very

I've maintained link integrity for a long time on my personal site using a similar tactic, however for me anyhow the new Wordpress version of the site had very little URL overlap with the old version so I just converted the old PHP version to static HTML and and set up nginx to serve both. When I migrate off WordPress, I expect I'll maintain a similar approach. No reason to maintain an older version of the site which could have security issues.