We have until the 31st Jan, though it is a "flextension", whatever that means. It is not like any of the extensions kept us in, we could have left at any point if we wanted no deal.
Actually, these extensions do keep the UK in the EU. Legally, a no-deal exit is only possible at the end of an extension and the period can only be cut short if a deal is made. This is nothing new, however, because even the initial two-year period specified in Article 50 could have been cut short by an exit deal. So, yeah, "flextension" is some kind of marketing term.