Rare 9 speed H pattern manual in a Hino Profia truck with 2 actual neutrals

It operates like 2 separate transmissions connected to each other. It's shifted normally up to 5th and to get it into 6th you need to put in neutral and smack the shifter to the right which really just a range selector. This pushes the shifter to the right and then you can shift into 6th and up to 9th vise versa.