H1Z1's latest patch, the one that will add playable female character models, has been pushed back to Friday, May 1st.
Developer Daybreak Game Company didn't give a specific reason for the delay, only saying "Things are coming in a little hot right now to patch tomorrow morning. We are going to move the patch to Friday morning."
The developer is still compiling the patch notes, but did confirm they will be released tonight. What we know for certain is that the update will add female character models, Steam Marketplace functionality, first person Battle Royale servers, and a higher res version of the interior for the Off Roader.
As a reminder, tomorrow's update will come with a complete player and server wipe. Like last time, all of your items that are tied to your account will remain, but all items in your inventory and player built structures will be reset.