We need to raise it about 50cm, but if we keep the same 45 degree angle it'll be up against the fence. I don't know how these things are used but is that going to be a problem?
Ideally I'd like to go straight up, but the fact that you don't seem to be able to get perpendicular access points suggests that it needs to be at that angle.
You could consider replacing it with an inspection chamber, which would go straight up, but would avoid the need for a bend that would make rodding difficult. These are the norm in plastic systems, but clay pipes seem to have rodding points. Not sure how easy it is to mix pipe types.
Inspection chambers are so much better in any system as you can use suction as well as rodding/jetting.
Rodding eyes are crap really and I wouldn’t have one in unless I really really had to.
Full disclosure - I am a technical specialist for a water company.
Is it foul or surface? Might need different approaches Do you know or could you measure down the RE to see how deep or how far to main run if not too deep or far dig down there use some slow bends eg 11deg to bend in chosen direction and level you can get clay to plastic adapters if needed or use a band seal
Oh I didn't know about inspection chambers. This is the standard 110mm plastic pipe in the back garden which is up-slope of where the foul water drains are so I don't think it's that. Plus doesn't smell. 15 year old house.
the fact that you don’t seem to be able to get perpendicular access points
I think you can, e.g. https://www.drainagesuperstore.co.uk/product/aco-rodding-eye-vertical-gully-kit-stainless-steel-304-vertical-outlet.html
Oh I didn’t know about inspection chambers
See here. then you'd need a couple of risers to bring it up to ground level, and blanking plugs for the entries you're not using. And a cover.