One year before my actual retirement (at age 60), I moved to part-time working, which gave me the opportunity to live within the income I believed I would have at retirement. At that time I had a small mortgage which was interest only - the idea being that I would be able to clear my mortgage from the tax-free lump sum I would be able to take at my retirement.
In fact, this worked out pretty well, although there was very little "extra" for things such as holidays, or any other large expense.
Despite of "life" throwing various "curveballs" at me (including the death of my mother, a late marriage, and a few other things), I am now reasonably situated (I have three small pensions), and am working on building more savings in order to feel a little more financially secure.
As has been previously pointed out, only you can know how much you need in order to live comfortably, and what you could "do without" if need be. Do your sums, and if (and only if) you are happy that you can live with limited means for the required period, then go ahead. There are considerable savings in not having to go to work (travel, lunches, clothes etc) and you can save a lot of money by finding new things to enjoy that cost much less than things such as theatres, cinema, drinks out etc., that may have been what you enjoyed with work colleagues. There are plenty of tips on frugal living on the internet (or in libraries, when available). Good Luck, whatever choice you make. It is only sensible to consider such things before retirement!