Generally speaking, you are bound by the by-laws that were adopted at your scheme’s first general meeting and then amended by special resolution at General Meetings and registered with the Registrar.
There is no automatic update, however, even if the scheme adopted the model by-laws as a package.
If your scheme didn’t formally adopt by-laws when it was formed, the “model” by-laws that were in the regulations at the time it was formed are adopted by default. Again, there is no automatic update.
Many schemes periodically update their by-laws to reflect the community’s wishes, changes in attitudes and new by-laws that have come into the model by-laws in the interim. But this has to be done by special resolution at a general meeting.
I believe there was an catch-all, manadatory update of all by-laws back in the 70s but I am a bit foggy on the details of that. I don’t recall anything happening in the 1990s.