I got fixed almost everything in SP_SEO plugin (buttons, query erros etc), but redirect doesn't work (it creates temp .htaccess, but it's not able to rewrite original .htaccess)
But it's too much for pure redirect plugin. I know very good solution in WP, maybe I will look how they do it.
For example: I deleted tags plugin and I have indexed links. I want to redirect them with 301 to pages or somewhere. When I saw SP_SEO on your site, I checked it and it did something like this. But it doesn't work in 2.1.7
This is just idea. I collect information.
This is related :
I am not able to "catch" 404 in e_module.php.
(it creates temp .htaccess, but it's not able to rewrite original .htaccess)
The solution was so easy that I can believe it.
I am not able to catch 404 yet, but I am able to do redirect with JM Canonical plugin.
I will add new field Redirect. If you set it ON, it will do redirect to Canonical URL. And because your canonical URL can be homepage, you can redirect them to homepage.
I will add the same field to Related Canonical URLs too. So instead deleting page, you will add redirect. If you delete page, you will add redirect via manual URLs.
It will need to add new tests:
source and result page can't be the same...