Don't neglect the L50 Darksteel Ore node at 1 AM after hitting the 11PM Adamantite one. There's good gil in Darksteel Ore, nothing else to mine at that time, and you won't need a cordial before or after - it's a 3-bell window after all. Plus if you want you can bring out your chocobo and beat a few Karakul down for their fleece while you wait for GP to recharge, the fleece is still worth a few gil.