Jubilee line DMI/Signalling problems?

All the CIS systems have default DMI messages if they lose data feeds. These can vary a bit, it depends if the feed is lost to a single sign or site or from a complete outage, and can vary from line to line. I can't say what the JL messages are. As has been said, each line has it's own control centre where raw data feeds are usually generated; the signalling kit at each varies, the central CIS kit at each site varies, the kit at each station varies, nice that it would be to have a universal standard alas technology and changing standards and project drift (and descoping !!!) over protracted time periods that run into decades means we don't and probably never will. The same is true of the internal trackernet system; the end users may perceive something universal, but believe me every line's raw data originates in a different way from different kit through much software twiddling to get there.