It’s funny you bring that up, because my friend moved a few months ago, updated address on the electoral roll, and his banks, who report to Experian, and there’s still no sign of his new address.
On the flip side, when I moved to Scotland, mine had updated the month after. I just blamed it on his council being slow, because when I moved around in England, some areas were very slow at updating the electoral roll records. I’ll suggest he check TransUnion now then, seeing as that works for you, so thanks for that!