@ BKK,
Probably. As always all human beings can and do make mistakes. The good news is that the Openreach engineer had the courage to talk to a stranger and then to realise what he had caused to happen.
Kind regards,
Walter
It's an unsurprising fact, that intervention in the network is the cause of a percentage of subsequent fault scenarios. Alas, we can't fully ever have a 'hands off network' (until we are fully fibre), due to constant changes in EU's needs. An example being 'Pair Diverts', where an EU requires extra circuits at their premises but the serving DP (Distribution Point) is at saturation.
The simplest way to fulfil the order (Where possible), is to 'Divert' a pair from another DP that has plenty of spare capacity.
Also, aluminium UG joints are a mare ............ it matters not how careful one tries, the chances are you mend one circuit and put a fault on another. Awful stuff to work with.
Great result with your issue though, Walter.