That needs a new consumer unit and, by extension of, a rewire. A mixture of cartridge and wire fuses does not meet current regs at all. Also no RCD and a Economy 7 timer?
Does this place have electric heaters around the house? I see what looks like a timer at the top.
I'm guessing one of the consumer units was a later add-on. It's possible that the tails that leave from the meter are split at one of the black boxes, and then feed both consumer units.
How does this look?
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