@ WinterJade - ED - erectile dysfunction, ejaculation disorder - admittedly 2 slightly different issues, but they can often feel like the same thing to a guy.
@ Mug81 & CcegG - unfortunately, that option doesn't work for us. I think my partner has a very low libido - he only wants to do it once in the month, so he holds out until O day. No fresh sperm here!! I have suggested not telling him when it is and is doing it several times around then-ish to take the pressure off him but he doesn't want to waste the effort if he actually finished. Always looking for the instant home run, rather than running between each base one at a time, so to speak. Part of the problem has been sleep deprivation - he's just too tired to BD all month long!