The Future Perfect Tense

Present perfect tense is something that happens at some time between the past and now. Future perfect tense is a kind of unspecified time, not a specific time. So imagine we're looking at a timetable like my plan for the day. I'm imagining myself being 80 and then looking back on the past. It's a bit of a confusing kind of time travel going on here. But maybe if you're a fan of science fiction and you like these kind of timeTravel movies, maybe it might be a bit easier to understand.