Fixed-term memberships last for a set amount of time and are paid for upfront in a single card payment. They give you unlimited access to your home gym and allow you to book classes 8 days in advance. At most gyms, you will also have access to all classes.
It's really important that you're sure which gym you want to visit and how long you want your membership to last for because fixed-term memberships cannot be changed once they've been purchased.
To find the fixed-term membership option, choose a monthly membership type during the join process and progress to the 'Payment' stage where you will be presented with the option to 'pay for a fixed-term membership by card'.