In it's current state (ie no day/night circles) Blockland is not suited at all to house something even remotely similar to Day Z. The ArmA2 engine is neither, actually.
Maybe once v21 comes out we'll be able to re-create it, but it still would require a forgetton of add-ons and a specialized zombie mod. Neither ZAPT nor Gamemode_Zombies are well suited to recreate DayZ.
Edit: This does not reflect my opinion on the server at all, though. I'll try to join if it gets hosted sometime, but I doubt it can catch and remake the DayZ experience.