Preserve the source representation
The project DTD describes compact date-time values and timezone information, with UTC assumed when no explicit timezone is supplied under that format. Do not replace that rule with an arbitrary local timezone because a channel is associated with a familiar country.
For a hypothetical listing, a start at 23:30 with a positive offset can map to a different clock reading and possibly another date elsewhere. The format value, conversion rule and viewer location belong together. A screenshot showing only 11:30 cannot support a reliable comparison when its date and zone are missing.
Adjacent boundaries need consistent interpretation
The DTD commentary treats start and stop as a half-closed interval when both are present: the start belongs to the programme and its stop is the boundary before the next one. This avoids inventing a moment of overlap between properly adjacent listings.
Imagine programme A runs from 18:00 to 18:30 and programme B starts at 18:30 in the same complete timezone context. A naïve inclusive comparison at both ends can show both as current at the boundary. A consistent interval model selects the later programme without adding an artificial gap or changing either source time.
Keep schedule and actual broadcast separate
A live event can overrun a published slot. That observation is not automatically a parser or timezone error. Compare several neighbouring listings before applying a global offset, and retain the exact transmission identity so a regional schedule is not mistaken for another feed.
For an authorised guide investigation, provide source values, interpreted values, date, timezone and the observed programme. A player can also have its own import or display settings that need product-specific documentation. This reference does not claim those settings were tested, that every player implements identical boundary handling or that a guide listing certifies a programme's actual on-air end.
Questions about this guide
Should a missing offset automatically mean my local timezone?
No. Apply the XMLTV format’s documented convention and the importer’s supported behaviour.
Do two adjacent listings necessarily overlap at their boundary?
No. A consistent half-closed interval model avoids that artificial overlap.