Outdoor Circuit?

[Ghacking]

Firstly, please excuse the volume of posts. I’m finally getting round to all the jobs I’ve been promising the wife for in some cases years.
i purchased a Knightsbridge IP663g outdoor switching box with the idea to run 2 small lighting circuits in my Bbq area approx 15 m from the house. The power would come off the kitchen ring via a fused spur on a 6a fuse, I’ll run a 1.5mm t&e to the switch box the 2 1.5mm t&e to the individual circuits . All the cables would be in 20mm heavy duty conduit.
She has now asked if we could add a socket to power an outdoor speaker or phone charger etc. Therefore my question is if I used a 13a fused spur and cabled to the box in 2.5mm t&e then ran 2.5mm from the 8a output could I power an outdoor socket?

ive attached a picture of the Knightsbridge box.

thank in advance

 

[SJD]

Wire the socket up first, on a 13A spur, then the switching box.

I'd avoid powering the socket via this switching box's 8A outlet. With the output limited to 8A, sooner or later someone will plug in something that takes more than that and blow the fuse. Plus my experience of these type of boxes in general is that the fuse doesn't always protect the switching, and it can be damaged anyway.