I am hoping to fly to Alderney on friday. Wx may not be too promising. If I understand it correctly one can ask for special VFR southampton-Ortac and go anything up to FL100. Might not get it of course!
Unless you are an IR holder you can't route SAM-ORTAC at anything above FL035 and then you'd be IFR not SVFR.
You can route from BIA down the West side of Q41 at any altitude you like VFR or IFR OCAS and you'll be clear of the Danger Areas too, they may well be active on a Friday, especially D026.
You'll need to contact Jersey Zone about 15 miles out and they'll clear you SVFR into the zone and give you an altitude.