Black Sheep do Openreach do the same as Cityfibre in that they dont look for wayleave on rented houses? But do on any address with flat in the name?
Openreach don't know if a property is owned or rented by whoever orders a service.
If there's no obvious wayleave required then they won't seek any additional permission forms.
Generally a wayleave is only required if a provider is installing hardware for which they may need future access, or infrastructure (including ducting) that will be used to serve others.
A drop cable tends not to need this if only serving the person who ordered, unless it's crossing someone else's property.
MDU's are treated different because there's almost always different legal responsibility/ownership than the person who ordered involved somewhere.
A single dwelling unit that can be from from the DP without crossing another property will go ahead without issue in almost all cases, regardless of the owner/tenant status.
It's cheaper to remove your CSP and drop cable if an owner/landlord complains than it is to check ownership of every property.