How are you managing to inject such a large quantity of lantus? I know some insulins have U500 versions (5 times the strength) so as to reduce the volume needed to be injected, but can't see a U500 lantus online.
Are you taking a fast acting insulin as well?
If I've understood your previous posts correctly you are still producing large quantities of your own insulin so insulin resistance is your issue? (Though I suppose the increase could also be explained by a sudden reduction in your own insulin production or some combination of the two factors).