DVB-SI date — 23 April 2038

DVB service information stores a date as a 16-bit Modified Julian Date. That field runs out of unambiguous values on 23 April 2038. Electronic programme guides and receiver clocks that trust the field are the exposure. Video and audio are not.

Standard	ETSI EN 300 468, date field in DVB-SI
Encoding	16-bit MJD. MJD 0 is 17 November 1858.
Last unambiguous classic value	22 April 2038 (MJD 65535)
Ambiguous day	23 April 2038
Proposed continuation	Values 0–32767 read as MJD + 65536, through 9 January 2127

What testing already showed

BBC R&D and Nagra reported in 2025 that test streams with post-2038 dates produced degraded EPG, parental guidance and clock behaviour on representative receivers. The picture and sound continued. That is the useful split: a “TV still works” result does not mean the guide or the scheduled recording still works.

DVB’s proposed mapping, in the BlueBook A038 work that followed DVB Scene 66, treats 32768–65535 as 5 August 1948 through 22 April 2038, and 0–32767 as 23 April 2038 onward by adding 65536. Receivers that do not implement that mapping will read 23 April 2038 as a 19th-century date.

Why a set-top box can hit two deadlines

This is broadcast metadata, not Unix time_t. A box can still hit both if it sets its real-time clock from SI time and that clock is a 32-bit counter. Test the guide and the clock separately. DVB publishes date test streams at dvb.org/date-teststreams; those are the primary artefact, not a blog recap.

Related records: Unix Y2038 on 19 January, GPS week on 20 November.