Afternoon,
I'm Yorkshire based, and we tend to do south coats or Scottish borders. The geology of the seabed doesn't really suit diving from the Humber up to the Tees until a good way offshore, but from Newcastle / South Shields you have Spellbinder. They do Wednesday afternoon Tech trips in 40-50m with ropes off about 6 if I remember correctly. Its arranged on Facebook by a local instructor, Tim Cutter. Above that, as Wibble says, Eyemouth and St Abbs. Both have boats and a great range of stuff to get to. West Coast has limited diving from North Wales up to the Scottish border, and there might be a boat out of Liverpool, but not sure. Its a pretty shallow gradient on the seabed, so long way out to get depth and very muddy bottom. You can pop across to the Isle of Man and there are a couple of boats from there and they have some good tech depth bits. Then up the Scottish west coast to the Clyde, then the Sound of Mull, both have some great diving. And on to Scapa which is great for a 45m accelerated deco trip.
Depending how far north you are, there's a lot of tech diving out of Portland, which if you're the wrong side of the Pennines can be done reasonably straight down the M6, Brum Box and A34, and you'll get 30-50m stuff often, we've got this weekend nicely in 42-43m for 2 wrecks off Scimitar.
Depending on you're club, it can be a nice project to get divers interested after one makes a leap and has an interesting and exciting season, then work other people up to it over a winter period for the next season. BSAC ADP is a good course, and Region has support for it in a lot of areas. There's a good amount of dive planning on FB if you look at the groups, and often spaces to jump on. No buddy can be limiting though.
Hope that helps, good luck! We have some great wrecks in that range.
Rich