I'm guessing that the 150's and 158's in works get done before the end of the year, leaving approx 8 150's and 3 158's to do, which equates to the extension for 11 142's until mid February.
Then the plan seemed to have 48 195 in service leaving 10 to introduce plus 11 156 still to PRM plus 5 further 769 (after 3 introduced) = 26, which roughly equates to 23 144.
Then the plan seemed to have 48 195 in service leaving 10 to introduce plus 11 156 still to PRM plus 5 further 769 (after 3 introduced) = 26, which roughly equates to 23 144.