Before you leave go onto your eOPF and make sure everything is correct, especially your last 5 SF50s. (Just in case by the time you collect the annuity the system has changed to a 5 year high.) Double check that they show your correct service comp date (start date) for both this job and any prior fed jobs. Same with any veteran status. Get them fixed if not, and I agree to keep copies of your last 3-5 SF50s.
This 2012 OPM brochure says you apply for deferred retirement by submitting a form at least 60 days before you want benefits to start. So it looks like you don’t fill anything out now, but you could email the retire@opm.gov address listed on the second page to confirm. https://www.opm.gov/retirement-services/publications-forms/pamphlets/ri92-19a.pdf
I have heard that you need to have ALL of your SF-50s from your entire career in case one of them goes missing from your OPF. Supposedly if one of them is missing, you don't get time served credit for the gap. Not sure if this is true or not. But it's easy enough to log on to your eOPF and see if they are all there. I downloaded all of mine for my entire 15 years of service, just in case.
Well that could take some time, but you are probably right...it will be worth having them if I do end up needing them.
Case in point, I made my military deposit 4 years ago with a different agency. This agency can't/won't add it to my LES because I didn't pay it here. But when I was trying to prove my case, I had my Paid in Full receipt and every single LES that had a Service credit deposit adding up to the full amount claimed. OPM seemed to indicate that having the hard copies will keep me from running into problems when I have to prove I'm done in the future.
Good recommendations, folks. I'll get to killing some trees.
Long retired HR Manager here. With regard to keeping ALL sf50s I think it depends on how complicated/convoluted your career has been. If you got hired and worked continuously for 20 years I'd only keep key SF-50s (hired, converted to career, last 5 years of any that affected salary). But some people have more complicated careers: multiple LWOPs long enough to require SF-50s, multiple types of appointments, many hirings and resigning, odd types of military time, etc. Then keeping ALL (minus crap like awards, WGIs, long ago across the board increases) could be warranted as a fall back in case your file burns and the computer is bombed.
Edited to add: Oops, I should have read all the way to the end. There wasn't an easy batch download option when I retired.