My ABS light came on, diagnostics said nearside rear sensor. I had the hub and sensor replaced but the light is still on! I'm coming up on my MOT and my garage (not Daihatsu specialisits) is now suggesting replacing the ABS pump because "what else is left to create the fault?" but this feels too vague (and expensive) to me. Can anyone offer any advice?

More info in case it's useful:
After the hub/sensor repair and several local trips with the light staying on, the light went out on a trip round our local ring road (70mph). It later came on again. The same thing happened a couple of times, then the light stayed off for 2 or 3 days, giving me the impression that it may be something that unseizes with the car warmed up and used more regularly (like many it has sat through the whole pandemic). I planned to give the car a run every day to test this but I unfortunately had to go away for a couple of days for a funeral, and the light is now on and staying on despite repeating a ringroad run.

I'd be so grateful for any suggestions/advice. The car is old and I can't pay for repairs "on spec", I need to feel we're on the right track to fix the fault.