Currently that version of the platform is not being supported so there is not upgrade plan to Kohana. In addition Kohana is also not being maintained so upgrading would not get you much support.
Have you considered migrating your deployment to the latest version of the platform?
There are two options for deploying the Ushahidi platform
1.You can sign up for a deployment on http://ushahidi.com. There are currently three different plans available for you to choose from
• Individual, which is free: For a single user who wants to gather one type of data and visualize it.
• Team, which is $99/month: For small teams who want to collect data and surveys via multiple sources.
• Organization, which is $499/month: For teams who want to triage and respond in real-time to incidents.
For groups running social impact projects unable to afford the current pricing model, you can apply for a free responder plan here: https://www.ushahidi.com/plans/apply-for-free
2.You can download the software at no cost and host it on your own servers. You can download the code from https://github.com/ushahidi/platform. Instructions on how to install can be found here:https://www.ushahidi.com/support/install-ushahidi
In the event that you would like to have our team install and customise the software for you, you can fill in our solutions form here https://www.ushahidi.com/solutions