basicaly its a late notified change – moving flats in the same blocj doesnt end HB, inmuchthe same way as moving from one address to another doesnt end HB – you need to figure out whethr the rent at the new place was more ofr less -0 basically if you are paying onLGHA , the HB wprobably wont change,, so the only thing that changed was the address.
HB would only end if you were aware of the move, suspended and asked, got no reply then termionated.
But I dont see what regs you are using to sday ” you moved out of dflat A in 2017, so thats it, you arent entitled anymore|”
of course if you did suspend, ask, get no response and ternminaye creating an o/p, then thats fine – but yes, you nmeed to award U/ent to the relevant periods
