Reddit mentions of Linx Linx 12X64-12.5-Inch Tablet with Detachable Keyboard Intel Atom X5-Z8350 / 1.44 Ghz (1.92 Ghz Turbo) Quad Core Processor, 4Gb Ram, 64Gb Storage, Windows 10 - Linx12X64

I have a couple that are ~400 pounds, tax takes them a little over.

https://www.amazon.co.uk/Acer-SA5-271-Touchscreen-Detachable-i3-6100/dp/B01KHTMXNK/ref=sr_1_19?ie=UTF8&qid=1543432679&sr=8-19&keywords=detachable+laptop

https://www.amazon.co.uk/Acer-Switch-12-2-Inch-Tablet-Processor/dp/B073WYB9YN/ref=sr_1_16?ie=UTF8&qid=1543432772&sr=8-16&keywords=detachable+laptop

Here is one under 400 but i'm not sure how good of a device it is but reviews say it is decent.

https://www.amazon.co.uk/Linx-12X64-12-5-inch-Detachable-Processor/dp/B06Y2W2NJX/ref=sr_1_9?ie=UTF8&qid=1543432840&sr=8-9&keywords=detachable+laptop

I compared the CPU's in them and by far the Pentium is the better option vs the Atom although the Core i3 is above them all.

https://cpu.userbenchmark.com/Compare/Intel-Atom-x5-Z8350-vs-Intel-Pentium-N4200/m143924vsm196248

https://cpu.userbenchmark.com/Compare/Intel-Core-i3-6100-vs-Intel-Pentium-N4200/3511vsm196248

I did some digging last night looking for a sub $250 2in1 that would work.

https://www.reddit.com/r/ShadowPC/comments/apcyao/looking_for_a_cheap_2in1_that_can_run_shadow/eg8b53r/

Edit: check out the Chuwi hi13. It's a big boy, but is £250 for a much better CPU, 3k*2k display, USB type C. It will have the power to output that resolution as well. It has the b/g/n/ac wifi, so you'll get a better connection as well. The type c with definitely help with getting an ethernet dongle as well.

Then theres the linx 12x64 that's only z£190 with a better CPU, 4GB of ram, twice the storage and a 1920x1200 display.

Maybe I'm just seeing the wrong prices since I'm in the states, but the linx 1010 on Amazon UK is £249. You have much better options than the 1010, unless you're getting a good deal on the 1010. I honestly would recommend getting something better in the display and i/O department. You're getting access to a comp that can throw 1440p at over 75fps, don't limit it with a bad connection and display.

https://www.amazon.co.uk/Linx-12X64-12-5-inch-Detachable-Processor/dp/B06Y2W2NJX/ref=sr_1_2?ie=UTF8&qid=1549115994&sr=8-2&keywords=linx+12x64

If I was using this as my main school computer while out of the house I'd want 4gb of ram. If I was using it only for Microsoft Office and was never connecting to the Internet I'd go with 2.
I did some research and this linx tablet is 200 discounted from 300. It has Micro USB charging. My last tablet had micro USB and it was so much easier than a DC jack. I carried a cable and a 20000mah battery bank from Xiaomi. I was able to go 2 10 hour days without a charge.
I honestly think this fits your needs (more so is safe for your concerns) I'd be a bitch to forget to back up something important and have a oem DC charger snap. I also have a soft spot for surface style to tablets and I'm thinking of having this shipped to America for myself. For £200 I don't think you can go wrong.

The linx 820 is 8 inches 2gb 32gb and its £170 so I don't think a standalone tablet is a good idea because those universal keyboards are uncomfortable. I vote this one I've linked mostly because of the surface style keyboard and the micro USB charging (this gets my vote x10 plus you can slowly charge it with any Android charger if you forget yours)
https://www.amazon.co.uk/Linx-12X64-12-5-inch-Detachable-Processor/dp/B06Y2W2NJX/ref=mp_s_a_1_1?keywords=laptop+tablet&qid=1569601307&s=gateway&sr=8-1

EBuyer has a similar 12.2 inch model for £190 and it also has micro USB charging but I think the processor in the one above is worth £10 more
https://www.ebuyer.com/845966-linx-12-2-inch-versare-tablet-4gb-64gb-with-keyboard-black-linx12v64blk-bun
I'm gonna vote tablet all the way so you can ditch

Well, I could - but a tablet is so much more convenient as a multimedia device. I initially wanted to spend £100ish on a tablet purely for Netflix and video etc, but then thought if I spent a bit more maybe I could have a more capable, portable secondary device for casual browsing or Word docs while sat on the sofa/train etc.

But like you say, I was wary of 2gb RAM on a Windows device, so it may be worth spending more on something with 8gb+ that I could use for more strenuous tasks. I just saw a few examples like this Linx that has potential, but that stand seems fairly pointless to me as I would rarely sit at a desk with one of these. Also this Lenovo MIIX 310 seemed good for the price with no need for a stand, and there is a full HD version of it somewhere. Just wondered if there's any worthwhile alternatives in the budget arena! But possibly not.

So perhaps I will wait for my Dell XPS 15Z laptop to kick the bucket as it still holds up fine, and then replace it with something decent. As currently spending £250-400 on a tablet hybrid would probably be more of a side-grade, aside from the size benefits.