Given as scheduled, per the source[1]: Stage One "will cost an estimated $33BN and will be finished by 2035," a target that depends on continued state funding for a multi-decade build.
Victoria's Suburban Rail Loop, announced in 2018 as a 90km orbital line built to connect Melbourne's suburbs without funnelling every trip through downtown, is aiming to open its first 26km stage in 2035. The state costs its first two stages at AUD $31-58BN; Victoria's Parliamentary Budget Office put the build at $125BN.