Q.Bird-of-Paradise (Strelitzia Reginae)
For official flower shows, the Strelitzia’s flower ideally is a 90-degree angle to the stem. Some flowers don’t grow this way. Is there any method to produce 90-degree angled blooms?

I know that with orchids, a grower can work with buds and stems on a 3-4 times daily to "straighten" or space blooms, by manually manipulating the bud or stem. I would think that you could attempt to do the same with BoP. If this didn't work, try a soft tape. Don't "encourage" (force) too much angle at once, you might break the stem. Don't wait until 3-4 days before the show. Start as the bloom spike emerges it's sheath.