Thank you for confirming.
Firstly, despite her abandonment without the relevant notice, you should be conscious that she has a right to remain in the property until formally evicted or until she has given the relevant notice. Therefore you should not be tempted to change the locks or remove her belongings if any remain. If you do any of this and reoccupy the property, or re-let it, then you will be at risk of her pursuing a claim for breach of contract and more importantly a criminal offence under the Protection from Eviction Act 1977 - this will be a costly issue if she pursues it and it will trump your rights under the agreement.
In the circumstances you should firstly request her to formally confirm that she has voluntarily vacated the property, despite not adhering to the notice period stipulated in the agreement. You can also consider pursuing a breach of contract for the remaining months.
If her formal confirmation is not forthcoming, then unfortunately you should pursue the legal steps to evict her - so service of Section 21 notice, and thereafter possession proceedings. I appreciate that this can be a long and costly way forward, but it is in your best interest to do this to avoid any claim by her.
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