Engines, in answer to your question,
I would very much hope that this SI on the DECU connectors was removed many years ago following corrective action to address the cause, or at least some palliative action in service (e.g. application of wire locking) to negate the need for in flight checks.
MoD's answer is that "
this SI was withdrawn from use in 1995 and the details incorporated into he normal Chinook Maintenance Manual". So it looks as though the connectors remained and the SI just became part of normal servicing.
DV