[guineapig]

Okay, so plane of Sky was introduced in January of 2000, 9 months after launch.

Patches from January 2000 - June 2000

Stand Out Occurrences:
- Plane of Sky is introduced (Jan.)
- Casters respawn with no mana after being killed by a player (Feb. 3)
- City of Paineel is introduced (Feb. 17)
- Erudites can now be Shadowknights (Feb. 17)
- Rogues get the Evade ability (Feb. 17)
- Deity-specific items are introduced (Apr. 10)
- Kerra Ridge and Splitpaw are revamped to higher level (Apr. 10)
- Kunark goes live with a new level cap of 60 (Apr. 21)
- Newbie guards get buffed to their current levels (May)
- The Hole is introduced (June 22)

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So this means that even though they mention changing the level of the Alter Plane: Sky spell on September 13, 1999, it didn't have anything to do with the actual launch of the zone. That leaves me with the following assumed release dates:


Temple of Solusek Ro: October 13th, 1999
Battle of Bloody Kithicor / Plane of Hate: October 31st, 1999 (estimate)
Plane of Sky: January, 2000
Kunark: March (or April), 2000
Ruins of Old Paineel (The Hole): June 22, 2000


If the server follows this time line we should be seeing the following:
(I rounded off to the month so in some cases it could fall on the month before or after based on the actual date)

Temple of Solusek Ro: early May, 2010
Plane of Hate: late May, 2010
Plane of Sky: August, 2010
Kunark: October, 2010
Ruins of Old Paineel (The Hole): January, 2011


Let me know if I missed anything

(EDIT: I have found conflicting information about Kunark being released in March of 2000 or April 2000, just an FYI)