Most modern hosts provide hosting with php setup as PHP-FPM(FastCGI Process Manager). This is pretty much the norm nowadays.
This provides a number of advantages. One example is that permissions generally don't have to be messed with except for executable permissions.
There are other advantages as well and my new update system will rely on one which is the ability to update files from the script.
So PHP-FPM is now going to be a hosting requirement for future versions of Cheetah. Updated hosting requirement page.
The old method of php running as an Apache module (also known as DS0) will no longer be supported.
It will be at least a couple of months before the next version is released, so there is time for those that are still using php as an Apache module to reconfigure their servers to use PHP-FPM.
One other requirement. PHP-FPM will need to be running as the same user as the user that uploaded the websites files. For most hosting that have Plesk or cPanel this is normally not a issue as that is how it's normally done by those hosting providers. This is a note to those that configure their servers by hand.
One way you can test is this.
Create a script. test.php and put this in it.
Upload that to the root of your website and go to it in your browser as https://yoursite.com/test.php
That script should copy your index.php to index.php.orig and then delete index.php.
If your server is configured as it should be, your index.php should now be gone and there should be a copy of it named index.php.orig which you can rename to get your original index.php file back.
Make sure you delete that test.php script from your server after your done testing it. You don't want it accidentally called by web crawlers as that test script has no security features built in to prevent unauthorized access.
If it turns out i am wrong and most hosts are not configured this way, then i will need to rethink things. But i believe this will not be a issue for most all modern hosting configurations.