Roof leak - possibly around vent pipe?

[DAVID CORKINDALE]

Hi,

There has been a recurring leak through our roof over several years - it seems to occur when the wind blows in a particular direction.
I have already attempted several 'fixes but I still cannot find the spot on the roof itself where the water is getting in.
I cannot access that part of the loft/attic as it is blocked-off by a brick wall.
Based on the photo of what appear to be Redland 49 tiles the chief suspect seems to be the area around the point where the vent pipe comes through the roof.

When I got up there it appears to be well-sealed with no obvious gaps but I wonder whether it was fitted correctly in the first place - does anything look 'off' about how it was left by whoever fitted the boiler?
The other thing is that the leak through the bathroom ceiling is lower down from where the pipe is in the next room, so I wonder whether it is feasible/likely that the rain water is pooling around the pipe, eventually leaking through a hidden gap and then running down the inside of the tiles to eventually come through the ceiling at that lower point? Thanks

 

[datarebal]

The lead under the tiles to the right of the flue needs to be turned up and back on its self.
The missing cut would be good too..
I don't think they are 49s fwiw

Ideally the lead would have been better on top of the tiles on the sides . A miscalculation on boiler flue length I guess

 

[catlad]

Looks like a plumbers effort! it should be inline with the pitch of the roof.

 

[Nige F]

But only a Registered Gas Installer may touch it ? Could be Marley Ludlow ? I don't think a plumber has been near it

 

[noseall]

Could be Marley Ludlow ?

Not with that more rounded curvy profile.