Ceiling light rewiring help - unusual old wiring

I have installed a couple of ceiling lights previously but have never encountered such a set up of wires for the old light. I am unsure which wires I need to put into my new light fitting.

I have attached images of both to this post. I have 3 red wires next to each other and then 2 black & 1 blue next to each other the other side. I also have the yellow/green earth wire which im okay with and then just 1 solid yellow wire which slots in next to the 3 reds.

Could someone please explain what each of these wires are (especially the all yellow one?!)

3 reds = Live
1 Green/Yellow = Earth
2 black = ?
1 blue = ?
1 yellow = ?

I would have assumed blue and blacks were neutral but was unsure as to why they were not either all black or all blue - and I have no idea what to do with the 1 yellow wire.

The above 8 wires somehow need to fit into a new fitting that just has 3 slots, 1 earth, 1 live and 1 neutral - any suggestions here very much welcome too (I'm assuming to get 3 into 1 I need some sort of connector?)

Thanks in advance and apologies for my absolute lack of knowledge!!

Edit - I have now added pics of the old wires as well as new fittings

The three reds are the "loop" these need to be kept connected together but not connected to the new light. The blacks and blue are neutral and the yellow live.

looking at the pic
3x reds looped in mains together
1xyellow light ( needs marking up )
2x blacks neutrals
1X blue neutrals
bloody Westworld beaten me to it.

Is there a loft space above there as you really need to put those cables into a joint box and then bring a single 3 core cable through for the new light as it's not designed for that type of wiring.

The Blacks and blue are all neutrals. The reds are all permanent lives and should be connected together but not to the light fitting. The yellow is the switch live.

If I were you I'd call an electrician now whilst it's straight forward for them to rectify.

Thank you for the explanations all - makes a lot more sense now I know what each wire is.

There is no loft space above as this is a downstairs light, but there may be enough space to either contain the joint box in the new fitting (not sire how big they are) or push it up into the ceiling.

I do have 2 more questions:

1. Regarding the 3 red wires - when you say they should be connected together but not to the light fitting, do i need to literally twist the 3 together and cover with tape, or is there another box I need to put them in?

2. Can I confirm that the live yellow wire is the correct one to place into the "L" slot in the new fitting?

Thanks again, really helpful.

No three reds need to go into a connector like a three way Wago or at worst a block connector. Yes the yellow goes to "L".

Pig Glider said:

1. Regarding the 3 red wires - when you say they should be connected together but not to the light fitting, do i need to literally twist the 3 together and cover with tape, or is there another box I need to put them in?

2. Can I confirm that the live yellow wire is the correct one to place into the "L" slot in the new fitting?

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it depends on the size of the tails are reds a wago should be used or what was said above .

buzzlightyear said:

it depends on the size of the tails are reds a wago should be used or what was said above .
View attachment 94068

Click to expand...

Ideal. I will order one of those for the red wires now.

As for turning the 3 neutral wires into 1 - do you know what is best to do this and do you have any links to such products?

Think this has saved me an electrician visit so much appreciated!

Pig Glider said:

As for turning the 3 neutral wires into 1 - do you know what is best to do this and do you have any links to such products

Click to expand...

to be truth full i would get a local spark in ,you would need to extend a link from this wago to the block connector neutral .
me thinks you will pull your hair out if you have some .lol.

As above but if you don't have solid conductors to make the link to the new light you will need these, it is five way as they don't do four way so your best bet is to use these for the reds also to save expense. The same applies to the earth as that green/yellow sleeving contains more than one wire hence you also need 2.0mm bore green/yellow sleeving to separately sleeve them.