Sent this to BBC Breakfast as a comment, don't expect they'll read it out so posting here. They're talking out the aging population and people working past retirement age:
The downside of working part time past 'retirement' is that the way many benefits and pension schemes are set up means that any income from part time work will be taken out of your pension or other income.
I do agree that older people should be allowed to remain in work, I'll be 40 next year and expect to have to stay in work into my 70s. Perhaps the way to deal with the perceived competition for jobs between old and young is to look at the younger end for changes. We're already part way into the change. Rather than expecting the majority of people to leave full time eduction at 16 or 18 we should be encouraging them to stay in full, or close to full, time education longer. This does not necessarily mean 6th form or university, it could mean vocational training, apprenticeship, voluntary work or a mixture of these.
This could be continued into adult life where people could be supported in taking career breaks to study for career changes or development. We've moved from one job for life being the norm to many jobs in a career for life, perhaps we can now move to multiple careers in a life.