VPN site to site with UTM devices to a 6600 Appliance

[ArathCG]

Hello everyone.

I have been working on the migration of Checkpoint technology, looking to jump from R 77.30 to R81.
One of the major migration bugs is that R81 no longer supports UTM devices.
I would like to keep them in the environment because they handle VPN site to site, how can I make this possible?
I would like to continue working on VPNs with these devices.