England - Joint periodic tenancy: one joint tenant gave notice, agent disputes it after we moved out and is claiming rent

Hi, apologies if this has been posted quite often, but I desperately need some guidance on this issue.

My former joint tenant and I are in a dispute with our letting agent over whether our joint periodic tenancy ended on 20 August 2026. We're looking for opinions from people familiar with tenancy law, particularly joint periodic tenancies, as we're struggling to get a clear answer and are now quite desperate to resolve it.

The tenancy originally started as a fixed-term AST in September 2024. The fixed term ended on 20 September 2025, after which the agreement provided for the tenancy to continue monthly. From 1 May 2026, our understanding is that the tenancy became an assured periodic tenancy under the Renters' Rights Act 2025.

On 12 June 2026, my former joint tenant gave the letting agent written notice stating that her two-month notice period would run from 20 June 2026 and that the tenancy would end on 20 August 2026.

The letting agent acknowledged the notice at the time and confirmed that, because the property was let as a whole, all occupants would need to vacate. The notice was never withdrawn, and my former joint tenant subsequently confirmed that she would leave on 20 August.

I wanted to remain in the property, so after the notice was given I tried to arrange a new joint tenancy with a replacement tenant. I did not pass the financial referencing requirements for the proposed new tenancy. A guarantor and other arrangements were discussed, but the proposed tenancy ultimately did not proceed. Nothing was signed or confirmed as having commenced, and the proposed replacement tenant never moved into the property.

Once it became clear that the replacement tenancy was not going ahead, I told the letting agent that I would also be leaving on 20 August in accordance with the original notice. It was at this point that the agent disputed the validity of the original notice and said that the tenancy would instead continue.

We therefore both vacated the property and returned all the keys on 20 August 2026, relying on the original notice. The 20 August date also corresponded with the end of the monthly rental period.

The agent has maintained that the tenancy continued into October. They initially said the tenancy would end on 21 October 2026, but later told TDS that they considered the tenancy end date to be 20 October 2026.

Their position regarding rent liability has also varied during the correspondence. At different points they said that, if I remained as the sole tenant, I would be responsible for the remaining two months' rent and bills; that the existing tenants were responsible for the whole rent; and that I would remain liable for rent and bills until 21 October if I vacated.

They have most recently referred to rent arrears and indicated that they intend to recover money from our deposit.

The deposit is protected with TDS. We raised a dispute, but TDS has now confirmed that it cannot determine whether the tenancy legally ended and that the deposit will remain protected while the matter is unresolved.

We have already contacted Shelter and Citizens Advice numerous times. Shelter previously explained that, if the notice from one joint tenant is valid, it would bring the joint tenancy to an end for all joint tenants, but they did not assess the specific notice itself.

I have also contacted the University of Manchester Legal Advice Centre and Greater Manchester Law Centre for proper legal advice. However, I'm getting pretty desperate with the situation and thought it was worth asking here as well in case anyone has dealt with something similar.

What we're particularly trying to establish is:

1. Can one joint tenant validly terminate a joint periodic tenancy by serving notice?

2. Does the particular notice appear to have validly ended the tenancy on 20 August?

3. Does the fact that the agent acknowledged the notice and initially told us that all occupants would need to vacate have any significance?

4. Does the attempted replacement tenancy change anything, given that no new tenancy was ever agreed or commenced?

5. If the original tenancy ended on 20 August, can the agent subsequently claim rent for the period after that date?

6. If the agent maintains that the tenancy continued until October, what would they need to do to establish that rent is actually owed?

7. Does the fact that the agent has given different explanations about who is liable for the rent have any legal significance?

8. Is there anything we should be doing now while the deposit remains protected?

We have the original tenancy agreement, the notice itself, the agent's acknowledgement, all subsequent correspondence and the TDS correspondence.

If anyone can spot an issue with our understanding of the situation, I'd genuinely like to hear it. We're mainly looking for informed opinions on what the legal position might be and what we should be doing next.

Also, if anyone knows of a solicitor, law centre, legal clinic or other source of proper housing advice in Manchester/Greater Manchester that might be able to look at the documents and advise us, we'd really appreciate recommendations. We've already contacted several places, but we're finding it difficult to get someone who can actually look at the specific notice and tenancy rather than just give general guidance.

Thank you!