Hello erg,:welcome:to the forum.
you will need to remove the skirting board to get access to underneath.
from the picture it looks like the piece below the shower is profiled around the skirting to the sides,
so it should come out with some gentle persuasion.
Remove the gripper rod first for better access, plus its not comfortable to rest your hand on
I would seal the shower first before starting to try and take skirting etc off. I've found that 99 times out of 100 it's the shower leaking somewhere and not the trap. Try standing in shower and spraying all around door and see if there's any damp showing. If you want to check trap spray into waste and nowhere else.
more likely than not the person who fitted the shower screen did not silicone behind that vertical channel the tray and tiles, they fitted the screen first then silicone after.
Big mistake, this is what it will look like when you take screen and channel off
this is actually a bath but the shower will be the same concept
more likely than not the person who fitted the shower screen did not silicone behind that vertical channel the tray and tiles, they fitted the screen first then silicone after.
Big mistake, this is what it will look like when you take screen and channel off View attachment 14598
this is actually a bath but the shower will be the same concept