Media diagnostics · Primary-source explanation; no UK IPTV implementation or account test. Instructions are based on publisher guidance; a UK IPTV account was not tested on this platform.
Recognise an ambiguous label
A schedule entry saying only 01:30 can be ambiguous around an offset change. The date, region and source offset supply context that the clock label lacks. This is different from ordinary subtitle drift or a player losing thirty minutes of media. Before applying a blanket hour correction, inspect the actual guide timestamp and establish which occurrence the publisher intended.
Calculate two hypothetical instants
Take an illustrative local time of 01:30 on a day where the offset changes from +01:00 to +00:00. The first occurrence at +01:00 corresponds to 00:30 UTC; the second at +00:00 corresponds to 01:30 UTC. They share a visible clock label but are one hour apart. This arithmetic example does not assert a particular country’s current legal clock-change date.
Compare the source and display separately
If two programme entries appear at the same local time, do not immediately delete one as a duplicate. Compare the complete source timestamps, titles and intended programme identities. Conversely, two different offsets do not prove that the source is correct; they simply make the intended instants distinguishable. A recording’s actual content and start time remain observations to compare with the schedule.
Provide a precise correction request
A useful report gives the date, intended timezone, original timestamp and displayed result, rather than saying every programme is an hour wrong. RFC 9557 explains that local times can map to zero or multiple instants around offset changes. Keep that edge case separate from an everyday fixed offset setting, and preserve the syntax required by the actual player and guide format.