Jimmy
I made the wrong reference. Its the Strata Schemes Development act 2015 Part 1 Preliminary 3 definitions
And whilst the Common Property Memorandum is widely used as the bible, even if a strata adopts it the SSMA overrides it.
The definition of common property depends on when the strata was registered. The 2015 Act identifies 1986 as the relevant date in th It is case
This is somewhat similar situation to the definition of common property that is applied to pre 1974 strata ( that is there are specific differences between pre 1974 building common property and post 1974 common property)
And my source of reference is Amanda Farmer. She discussed it at length on two of her podcasts.