When you added a video to your Story it was split into 15 second segments which then allowed you to add text and stickers to each segment but it was always a bit annoying. Your video always looked a bit jumpy as moved from one segment to another. Over the past few months Instagram had been testing sharing 60 second videos without splitting them and it has now started rolling this out to all users worldwide. If it isn’t yet in your account it will be shortly.
Just last month it announced that all videos less than 15 minutes are now Reels. The big picture here is that Instagram is trying to standardize video within Instagram and everything is moving to vertical video that eventually could end up in the one feed – Reels, Stories and Video Posts in a single immersive feed that would be similar in experience to the TikTok feed.
All the best