alt Hacker NewsYes, though I'd be careful about assuming that votes are Conservatives <-> Reform on a left-right median voter model. The other aspect that Reform has (and will have at least until it forms a government) is anti-system/populist credentials. Labour had a little of that last time (they are a deeply establishment party, especially under current leadership, but they were coming off a period as very public opposition to the government and the current state of things) but will have very little next time.
It's certainly not a given that all the 2024 Reform vote would have gone to the Conservatives: a good chunk of it would have likely been disgusted abstention, another chunk to other anti-system parties (mostly of the right fringe, I suspect, but not excluding the Greens despite wild ideological differences), and likely a further (if smaller) chunk to other parties which were simply not the Conservatives (including Labour and the Lib Dems).
Edit: the best analysis on this is likely to be in the latest volume of the long-standing The British General Election of XXXX series, which has just been published online[0]. I haven't had time to look at it yet, though.