My two cents about Pre-load/release Exact time
Preload time

https://www.timeanddate.com/countdown/generic?iso=20180807T21&p0=215&msg=Guessed+MHW+pre-load+time&font=cursive

Font:
The amazon.com MHW pc page show it as a delivery time:

https://www.amazon.com/gp/product/B07FMDX8LQ/ref=s9_acsd_newrz_hd_bw_b14HgzT_c_x_w?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=merchandised-search-6&pf_rd_r=9FPXC2VA6QTG3NDBQEJA&pf_rd_r=9FPXC2VA6QTG3NDBQEJA&pf_rd_t=101&pf_rd_p=110821e0-3869-4012-847d-cede7e7106ed&pf_rd_p=110821e0-3869-4012-847d-cede7e7106ed&pf_rd_i=979455011

Release time

https://www.timeanddate.com/countdown/generic?iso=20180810T02&p0=215&msg=Guessed+MHW+release+time&font=cursive

Font:
The official schedule let start every "week" on fryday 0:00 UTC

http://monsterhunterworld.com/eventquest/MHW_EventQuest_EN.pdf

Let me know what do you think about it!
Cheers!

https://www.timeanddate.com/countdown/launch?iso=20180809T00&p0=234&msg=Monster+Hunter+World+Global+PC+Release&font=cursive&csz=1