If they are moving to a new cabinet, speeds will slow whilst the cables are teed up to both cabinets.
If there is a polarity reversal on a jumper at either cabinet it will cause a loop fault whilst both cabinets are teed and jumpered
I would guess they pulled the jumper at the old cabinet to cure your fault.
A 12 vert cabinet reload could have around 19 thousand terminations on the job. They will get a few wrong.
Edited by partial (Sat 25-Feb-17 12:31:06)