quest: import #7965, flag the TS PCR only where its clock jumps

quest/m1/ts-reliability/README.md

@@ -125,7 +125,9 @@ two outages); state stays bounded by the track count, and the extra flag
 lands where loss happened. Not chosen: keeping every loss until all tracks
 pass it (unbounded while a track stalls); collapsing losses older than the
 release point minus the delay (more code, and assumes muxing in release
-order).
+order). Reversed the same day: the planned
+[PCR jump flag](/quest/m1/ts-reliability/pcr-jump-flag.md) removes the
+per-track loss tracking.
 
 PMT fragmentation (#5220), initial mux-rate measurement (#5287), and
 decoder-time admission (#5306) have landed, as have PSI runs (#5606) and
@@ -134,8 +136,8 @@ catalog linger (#5305).
 ## Required
 
 - [A CBR import's muxRate can't stick low](/quest/m1/ts-reliability/mux-rate-raise.md) - a stable window above the published rate raises it, and an export's deadline miss names the rate it needed
+- [The TS export flags a PCR only where its clock jumps](/quest/m1/ts-reliability/pcr-jump-flag.md) - a padded skip goes out unflagged; a schedule that skips slots flags the jump
 
 ## Related
 
 - [MSFTS mapping](/quest/m3/msfts-convergence.md) - document the exact equivalence and differences between the carriage modes
-

quest/m1/ts-reliability/pcr-jump-flag.md

@@ -0,0 +1,44 @@
+# [S] The TS export flags a PCR only where its clock jumps
+
+## Goal
+
+`moq export ts` sets `discontinuity_indicator` on a PCR exactly when the
+time base it asserts breaks: a declared switch, as today, or a schedule that
+skips empty slots so the PCR jumps past the bytes between. A delivery skip the
+schedule pads on a continuing clock goes out unflagged, a gap in the programme
+and not a new time base.
+
+## Plan
+
+Reported in [moq-dev/moq#7965](https://github.com/moq-dev/moq/issues/7965),
+a correction to [moq-dev/moq#7741](https://github.com/moq-dev/moq/issues/7741):
+in a live relay-kill run the export padded a 7 s outage with nulls on an
+unbroken 25 ms PCR grid, and every PID's DTS kept its offset to the PCR. So
+[moq-dev/moq#7785](https://github.com/moq-dev/moq/pull/7785), which flags
+every delivery skip, declared a new time base equal to the old one there.
+Verified against `main`: the claim holds for holes the schedule pads, but
+`Schedule::index` (`rs/moq-mux/src/container/ts/schedule.rs`) skips the
+empty slots of a gap longer than `BACKFILL` (1 s), and that PCR does jump.
+`a_skipped_group_flags_the_clock` runs 6 s holes through that path.
+
+Decided 2026-11-05 (maintainer, /quest-import of #7965):
+
+- ✅ Flag real jumps only: derive the flag from the schedule, set on the first
+  PCR after it skips slots, whatever caused the gap, so a source stall with
+  no delivery skip is flagged too. Delete #7785's per-track loss tracking
+  (`Track::{gap, last_timestamp, lost}`, `coalesce`, `Queued::gap`,
+  `PesUnit::skipped`, `Schedule::{gap, skip}`), and the 2026-11-05
+  coalescing decision in the epic README goes with it. Not chosen: keeping
+  the flag as a skip marker and rewording its docs (it misstates the time
+  base); reverting #7785 (a hole past the backfill would again carry an
+  unflagged PCR jump); won't fix.
+- ✅ m1, in the TS reliability epic.
+
+Rework the tests to match: holes the schedule pads carry no flag and keep the
+PCR's repetition health clean; holes past the backfill carry one flag each on
+the first PCR after the jump. Fix `doc/bin/cli.md` and `test/ts/README.md`,
+which describe the skip flag.
+
+## Closes
+
+- [#7965](https://github.com/moq-dev/moq/issues/7965) - `export ts`: the skip #7741 reported keeps its clock