(1) This Act applies -

(a) from a date to be prescribed (being a date before 23 March 2007) to undertakings with at least 150 employees,

(b) from 23 March 2007 to undertakings with at least 100 employees, and

(c) from 23 March 2008 to undertakings with at least 50 employees.

(2) The number of employees referred to in subsection (1) is referred to in this Act as a "relevant workforce threshold".