When a complex is sold does it void tenants leases they already have in place?

The new LL (landlord) does not have a contract of lease with you, the old LL does. You have a right to remain under the old lease but, the likelihood they will agree to a new lease in May is low. The new LL is purchasing the property using financing. Having your lease improves their look to the new lender.  As long as the terms of the new lease are OK with you, all you are really doing is extending to the end of June which is a enough time for you to decide what you want to do. It could be the LL is looking to raise rents right now; again the lease they offer will tell you if they want to keep you as a tenant or not. Again, you don't have to sign the short lease but they will appreciate it if you do. Best of luck to you.