MySQL 5.6 Upgrade Issue

Hello,

we are currently running a debian 7 managed server with Plesk 12.5, PHP 5.6 and MySQL 5.5.
Is it possible to upgrade MySQL to 5.6? Our hoster tells us it's not possible without destroying the plesk installation. But the Plesk 12.5 with Linux documentation says MySQL 5.6 is supported.

So what's the truth? Thanks in advance!