I'm doing some DIY and came across some ceiling wiring I wasn't expecting. I'm changing a ceiling light and I've got three cables for this ceiling rose. One seems normal (left cable), LNE, but the other two seem unusual. The cable feeding into switch live (right cable) also has a black wire in the neutral block. There is also one sole live cable (middle cable) feeding into the loop without any earth or neutral. Everything's working as it should be but I want to attach a new metal lamp and I'm a bit weary. Can someone break down for me what's going on here and whether the absent earth is a concern?