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Can you confirm how long the ex partner has been living at the property for?
If the tenant has absconded and left the property, then you can go ahead and have a tenancy agreement in place with the ex-partner. Please remember to serve the usual documents - how to rent checklist, gas safe certificate and valid energy performance certificate with the deposit going into the a recognised tenancy deposit scheme.
If the old tenant is going to court in July to stop her having access, then that will be between them and this will have no affect on you as a landlord. Should the ex partner also vacate, we can chase for a s8 notice (rent arrears).
I hope this helps and please leave positive feedback. If I can assist with anything else, please do let me know.