Thank you for reaching out to us, and apologies for the late response.
We would be more than happy to help with this, to see if we can get a hot water boost switch installed for you. The best people to speak with, would be our New Connections team, since they manage this side of things. You can reach them on 1800 680 430.
I hope this helps, and please let us know if anything else comes up. 🙂