I don't know Grimsby.. wasn't even aware they did a degree, so can't help you there. I'll ask amongst my colleagues, see if they know anything about the course.
Being a BA in Commercial photography, it will be more technical than most other degrees, but having said that, degrees are not training courses. If you imagine you;ll be in studios al day doing technical stuff, think again. Degrees are academic. You'll spend a great deal of time in lectures, and a great deal of time in crit. That's what degrees are... academic. They are not designed for beginners. They're designed for fairly advanced students who have done foundation courses and already have a fair degree of experience. They are not training courses however. There will be an expectation that you are shown something, and you then take it upon yourself to develop that skill. IF you are passive, and just sit in lectures and do no work, you'll not cope with it.
The emphasis will be on skill acquisition in year one, possibly year 2... but as with photography itself, the emphasis will be on business skills and self development. This is one of the things mature students often dislike about degrees: They expected training, and got an education instead.
Would you be accepted? No idea... that will be down to you and your portfolio. If it's good, and you give a good account of yourself in interview, I don't see why not. If you're genuinely passionate about photography, quite a lot of mature students are accepted as they usually take this a whole lot more seriously than the average 18 year old. I certainly wouldn't be worried. Also, entry requirements are more relaxed these days. I'm not saying Unis will take anyone, but they certainly can't pick and choose any more.
Yes... all degree courses are different. They'll have a broad basic outline that matches QAA benchmark guidelines, but other than that, the degree is written by the staff at Grimsby, then validated by Teeside. Their degree will be very different from ours, or anyone else's. Go along, meet the staff, speak to students, look at the facilities. Decide if you want to spend 3 years there.
Most of the technical stuff you'll learn is available free, online. JJDiamond is correct. What you'll not get is the support in understanding it, and the facilities to practice it. What you'll also not get is being part of a creative community with one common purpose. Never underestimate what a powerful thing that is. Do it alone, and you're doing just that... doing it alone.
Ask if they have a visiting lecturer programme. This is crucial, as you need practitioners from outside the Uni to come in and see your work, and talk about industry. If they don't have a VL programme, they may well be worth a miss. For instance, recently we've had Dean Chalkley, Tim Flach, Dominic Rouse, and just last week Sir Peter Bazalgette, chair of the Arts Council, and probably the most influential person in TV today in to talk about entrepreneurship and funding for creative arts graduates. Events like this create networking opportunities, and give great insight into industry that no amount of YouTube can provide. If Grimsby don't have stuff like that, ask them why not. Any decent degree should have a budget for VLs. Times are tight, and many places... ours included, are cutting back to the bone, but that shouldn't be an area that's cut back.
As I said before.. a commercial degree should have high end medium format digital gear, as high end commercial photography uses it. It should include a great deal of lighting education and include things such as set building if it is genuinely a commercial course. It should also cover large format cameras, as these are used extensively in commercial product and architectural photography. They should have a well equipped library. They should have dedicated digital darkrooms with calibrated gear, not just a bank of Macs in a brightly lit classroom.... , and high end printing output too. You need to ask them this. Don't be too passive because you feel you are not degree material due to being out of education for a while. Don't be feeling grateful if they offer you a place and blindly accept. It's a 2 way thing... they have to be right for you, as well as you being right for them.
I want to gain more knowledge in photography in general, Gain skills I currently don't have - and have access to equipment I don't have.
Just be careful you aren't going into this expecting photographic training... as that's what you will not get. This is higher education, not vocational training. Lots of reading and research. You'll not be judged on just your images... you'll be judged on the research and rationale of your images. Turn in a set of superb images for an assignment with no research or rationale, and you'll still probably fail, or get a low grade. Think about it - if you take a maths exam, you'll need to show your working out to prove you never used a calculator, right? Well, this is the way you show your "working out" on a degree photography course. Anyone can take sharp and technically good images. It takes a few months to get someone up to speed with that. At degree level you need to have those images actually do a job... sell a product, tell a story, illustrate the intent of a fashion designer... whatever area of photography interests you, your images will be critiqued to a level you'll simply not get in here, and they'll be looking for a whole lot more than sharpness, exposure, and composition. So it wouldn't surprise me if there are lectures on wide ranging subjects that will educate you on what you should be shooting as well as how you should be shooting it. Photography will probably account for around half the course content. The rest will support your ability to be a critical thinking practitioner.