Formalising rail replacements

[Gazza]

Just a thought bubble, why can't rail replacement buses used during trackwork (And GCLRT replacement buses) have route numbers Say in the 900 series like Perth, with official maps published. Given shutdowns occur on uniform sectors these days, you could have clear guides/maps of the replacement bus routes for each sector (For instance when several routes are used with some being express to outer stations) temporary stop locations. Etc.
This would allow better preplanning by passengers, and would avoid the situation where people struggle to find the right replacement bus to use when multiple ones are operating.
Translink/QR would just link to these preprepared guides each time a shutdown happens.