That's the fun part!
This is 'primary legislation' - that means legislation that has passed parliament and been debated 'fully' by both houses.
What sets the actual rules is secondary legislation - this can be passed with little or no scrutiny, and require a majority of MPs to vote against it in a seperate vote that the MPs initiate later, only once it's passed.
The only limits to this are if the primary legislations limits cannot be read in a way to cover the powers required.
However, in this case, the definition of 'operator' is 'a postal or telecommunications operator', and that is further defined as 'someone who provides a postal or telecommunications service'.
Which is comedically vague, and can be (without violating the terms of primary legislation) read to mean anything from large ISPs to individuals controlling open source projects.
It most certainly - for example - includes people who operate random wifi hotspots who may be required to install certain software or do certain things.