McKenzie's amendment would push the state pension age increases back out to 2022, but this is likely to be dashed by the House of Lords shortly - probably on Monday.
Originally, many hundreds of thousands of women faced an extra two-year wait for their state pension, though the government has already wound it back to an 18 month delay.
"Ultimately, the government made a modest concession to the timetable, originally decreed that state pension age would hit 66 in April 2020," says Tom McPhail, head of pensions research at Hargreaves Lansdown, "but after a considerable amount of lobbying, it conceded a slowdown in the timetable, back to October 2020."
Equality or special treatment?But behind this is a bigger story. Between 2010 and 2020, many women will see their retirement age shifted by six years, to 66. Men, on the other hand, will have only experienced a 12-month extension to when they can claim the state pension.
Do women, then, deserve special preferential treatment here? Or should they simply be given what many have striven for over many decades - complete equality.