Locked out of ownCloud due to change of PHP version - upgrade or new installation


I just changed the PHP version with my provider to 7.2 and was therefore locked out of my ownCloud (9.x version). I cannot downgrade the PHP version, so what I need is an upgrade or new installation of the latest ownCloud version.
However, as I am using a hosted webspace, I have no server access, so the only ways are uploading/changing files via FTP and a new installation using the browser based wizard, which I haven’t managed to find among the downloads as well.
Can someone point me to the necessary resources, please.
Thank you very much in advance!


As far as I know you need command line access to upgrade ownCloud, but I might be wrong.