Mine is due in Saturday as well. By then I'll have a better handle on my needed amounts. I was kinda in "oh crap" mode last night when I discovered I've used about half of both bottles in 24 hours as I filled before bed. After a good night of sleep I realized it's because I filled 3 tanks of each type (2 spares of each) yesterday and vaped on a tank of each all day. I've got basically 3 full tanks of each this morning.