HB Claim ended - are they right

I have a client who will be worse off on UC due to the circs of her family. She has moved within the Local Authority in ALMO property and they are refusing to continue the HB claim. They have stated:

“Her Housing Benefit is not continuous, there is a break between the 22/03/21 when her old tenancy ended and the 09/04/21 when she physically moved into her new property. She informed on the 08/04 of her intention to claim HB for the new property”

The client was given use and occupation of the old tenancy until she moved but signed on the 22nd for the new tenancy. 
Is there any way around this?

EDIT

Sorry to clear this up -

The client is a secure tenant at address one with the ALMO she is moving properties within the ALMO as she was overcrowding in address one. Tenancy for address one ends on the 22/03/2021 and starts for address 2 on the 22/03/2021. The client stays in address one until the 09/04/2021 and is charged use and occupation. She notifies HB on the 08/04. They make the decision re HB and close the claim. I’m aware this is out of the one month time scale but have a strong out of time argument with local HB team

I think we need some more information about:

(1) What actually happened in relation to the two tenancies?

(2) When was the decision in relation to HB made?

Then no they aren’t right.

She was entitled to HB in respect of address 1 until 08/04 and thereafter was entitled to HB in respect of address 2.

She does not appear to have any entitlement to HB for address 2 for the period between 22/03 - 08/04 when she was not yet resident.

During the period between 22/03 and 08/04 , she still had a liability for rent as far as HB was concerned because a liability for use and occupation or mesne profits still counts as rent for HB purposes - see reg 12(1)(b) and (c) HB Regs 2006.

(I think that strictly this is a case of mesne profits rather than U&O because the claimant is a former tenant who failed to leave upon the end of their tenancy, although it doesn’t really matter)

However - even if that were wrong and there was no entitlement for that period - it is still important to establish when the actual decision to end HB was made.  This is because if the decision to end the HB was made after the entitlement had resumed in relation to property 2, the entire matter could be dealt with as a closed period supersession and HB entitlement could be preserved. That is because the decision maker needs to look at the facts down to the date of their decision - identifying a past period of disentitlement does not have the effect of ending the benefit award entirely if the claimant has re-established an entitlement by the time the decision itself is made.