Having looked more deeply into the 'hypothetical calculation' I have come to the startling conclusion that (almost) EVERYONE who is no longer in the final salary scheme should take a break from the TPS NOW! (*note I take no responsibility if I am wrong - do your own research to see if it works for you) Having just had a discussion with TPS the two schemes (final salary and career average) are treated separately. Because of this I conclude anyone who has final salary benefits but is no longer in that scheme should, if they haven't already, opt-out for a month immediately for the following reasons: 1) Future service in the career average scheme isn't affected (you lose one month's value to your CARE pension) 2) Your number of years service is already fixed (to the point where you entered the CARE pension) 3) Your best final salary link will be preserved 4) Your 3-in-10 salary will be worked out in two ways, 2009-2019 (ten years back from when you opt-out) AND whatever your last 10 years will be when you actually stop work - you get the best of these! (This is the main reason for opting out for a month now) 5) I have checked that opting out for a month DOES trigger the hypothetical calculation. 6) The comparison of pensions does not include the CARE benefits - so the final salary cannot go down by taking a month out now. And neither can your overall salary once combined. I would repeat you should do your own checking and get in writing from TPS confirmation of the above points.