There is no legal impediment for the time being to a residential landlord giving a tenant three months' notice to leave (see https://www.breakinglaw.co.uk/2020/03/covid-19-repossessions-halted.html) so that they are in a position to start possession proceedings if the tenant stays put when the freeze on bringing proceedings thaws out. The changes which the landlord will need to make to the prescribed form of notice are set out in the Coronavirus Act 2020 at schedule 29!! But let's hope that, in theses difficult time, such disputes between landlord and tenant as exist can be settled amicably.