Confidence
Direct sources
We assume ~2.5 min per relic opening (short fissure). Per-mission timings are labeled by source: derived from game mechanics or community-estimated.
Expected runs = 100/chance · Runs for confidence p = ⌈ln(1−p)/ln(1−chance)⌉ · In a squad of 4 opening the same relic, the chance your part shows among the reveals is 1−(1−chance)⁴.
Each run has a 38.72% chance. The curve is 1−(1−p)ⁿ: there is never a guarantee, only growing confidence.