The level of control exercised by the client over the services which are to be provided, as well as the manner in which they are provided, when they are provided, and where they are provided is very important for determining IR35 status.
It is acceptable for a contractor to mutually agree to execute a set task at a time and location specified by the client, but they should not be subject to any control or supervision from the client; it should be clear that the contractor is able to execute the work according to how they decide. Alternatively, an employee will probably have set times and locations for work; as shown in the case of Morren v Swinton and Pendlebury Borough Council (1965).
Having said this, in order to show that control is present, it needs to be a lot more than just shallow monitoring or reviewing of outputs. As per the case of [Chaplin v Australian Mutual Provident], unless the contractor is tied "hand and foot" to the client, control would not be so much as detrimental.