For me, most of the seed pods we get each year start in the late summer/fall. Many folks are concerned that their newly-formed seed pods will not survive a cold winter. However, plumeria seed pods have thick skins and will continue to slowly develop over winter.
Seed pods take 8-10 months to mature. So make sure that before 8 months, you cover it in some type of net bag to catch the seeds when it opens. Vegetable bags from your grocery store’s produce section work great. Others use pantyhose.
Of course, things can go wrong and some pods will rot over winter. Some are just weaker than most. Not much you can do about that unless you bring it in to a dry environment.