Cable visibility: Cables visible in 16mm nylon flex conduit leaving the cupboard. Cables turn to run up the wall 4-inches from a door frame. Cables run up the wall outside the 150mm zone.
Q - is a cover-plate required to indicate cable run?
Q - must it be at the 90-degree turn or can it be higher?
The area is covered by irreplaceable italian tiles on board. The board sits on 18mm of plaster within which I have eroded a cavity throughout the route via door frame access (keyhole work). This 18mm depth permits 16mm nylon flex conduit to assist in the spacing of cables, protection in the gap & on CU cupboard exit. Conduit remains 4-inches from the door frame re "big screws".
I am certain a cover-plate is required. However I can see no reason why it can not be at the 90-degree turn at the top (not tiled) which would indicate the turn & drop location whilst the CU cupboard end clearly indicates entry.
Coverplate could be a 1G PVC box sunk with 2 fully-slotted sides, or (perhaps better) a 150x150mm adaptable box cut down in height with nylon posts to permit a flush 160x160mm lid on top. Any cross bonding would be with 4mm ge/ye back to CU in this instance.
Putting a cover-plate at the CU exit seems a bit redundant, it merely says "cable turns up before door 4-inches to the right".
Putting a cover-plate at the top seems preferable, it says "cable runs along false ceiling here and drops down here". Entry at the CU below confirms entry location & purpose.