It appears that if you want a sequential callsign, you can apply for it online and get it the next working day. Vanity callsigns take 18 days. I again looked into the status of Region 0 callsigns and found this interesting set of facts.
1. Group A 1x2 and 2x1: Give up. Not worth fighting over. If you are competing with anyone other than yourself to get one, it's not when you applied, its 52 card pick up. IOW, a random assignment.
2. Group A 2x2: It's up to AD0U- and will take some time to get to AL0ZZ, when the system will begin assigning Group B 2x2 calls, starting in KI0T-.
3. Group B 2x2 K prefix: Just about any callsign past KI0TI is available. There are calls between KA0AA and KI0TI that were not used for some reason, and lots of previously owned calls available.
4. Group B 2x2 W prefix: Wide open, very few vanities.
5. Group B 2x2 N prefix: Wide open, very few vanities.
I won't even bother with Group 3 (1x3) and Group 4 (2x3). The point is to get away from those two group and have a callsign NO ONE has ever owned.