I’m guessing the patio is common property for the sake of maintenance and repair but you have exclusive use of it as implied in the strata plan.
Have a look and see if the balconies aren’t also common property (as they are in most modern buildings). This is exactly the same arrangement as operates for them, the only difference is that open landscaping makes your terrace look like it’s a community facility.
So if your neighbours are intent on resuming your patio, ask how they intend to allow you to use their balconies for barbecues and drinks in the coming months. What’s sauce for the goose …
The Owners Corp has an absolute responsibility to maintain and repair common property. If they force you to take this to the CTTT they will lose. Tell them to stop being so bloody selfish or you will take action at the CTTT to show that the Executive Committee and Owners Corp is dysfunctional and have them replaced by a statutory strata manager.
Or you’ll be having sunset drinks on a different balcony every night for the rest of the summer.