Ms Marsh has urged councils to act cautiously following the Lords victory. Teachers may claim breach of contract if they are asked to undertake duties for which they are not paid.
The millennium review was set up as a joint investigation with the teaching unions into the management and funding of education into the next century. Among its four tasks is an attempt to reach agreement on the management structure of schools, a central issue behind the SSTA's battle with the authorities.
Council leaders want more local flexibility to decide on pay levels and promoted posts, but the unions are suspicious.