I have sold a
property with a tenant
in situ.
It was simple enough, I sold it subject to (i.e. with) the tenancy and tenant in place. The flat sold to an investor/landlord, so for him it was perfect, and all the tenant had to do was change her standing order.
I go back to my earlier point, you can't (as a landlord) just summarily terminate a contract, you have to have contractual grounds (for example non-payment of rent, causing noise-nuisance 'out of hours' to neighbours, using the premises for immoral or illegal purposes, and so on).
It is for the landlord to explain any grounds they have upon which to terminate you early. So whilst wishing to understand the law of 'Landlord & Tenant', I'd in parallel ask the landlord what their Grounds are.
The below links might provide you with some general background information. They are sites based upon UK 'Landlord and Tenant' law; but they are relevant as a lot of Singaporean law is based upon UK law. [So consider the principles involved and represented, to get a solid feel for the direction of the wind, and then if necessary dig for the specific Singaporean laws].
http://www.landlords.org.uk/library/ten ... harassment
http://www.landlordaction.co.uk/site.php
Good luck, and keep us updated on how it goes.
p.s. Another option is to get a solicitor/lawyer to write a 'heavy artillery' (i.e. cease/desist/suggestion of harassment and possible civil action if it continues) letter to the landlord. It might cost you half an hour of the lawyer's time, but it might just be enough to get the landlord off your back.