Renewed Tenancy

I have just been informed by the rental company that I use that the initial 12 month rental period is coming up and we can renew at either a new 12 month period or month by month. This is all fine as the tenants are good.
They have however informed me that I will need the electrical certificate before the April deadline as it is a new tenancy. Is this correct?
Appreciate any feedback. Thankyou