Need help with a complicated conditional

[tribedude]

I currently have a forum with conditionals running to show a leaderboard (ADVERTISEMENT A) below the navbar to members or else it show 3 box ads (ADVERTISEMENTS B) to other user groups.

<!-- MAIN FORUM TAG -->
<if condition="$forumid == '14'">
<if condition=" in_array($bbuserinfo[usergroupid],array(30,9))">
ADVERTISMENT A LEADERBOARD
<else />
ADVERTISEMENTS B 3 BOXES
</if>
</if>

^ is working fine.

But I need to use this and ALSO incorporate a dateline conditional to display different ad types based on the date the thread was started?

For example, I want to show members the leaderboard ad as I am doing above, but if the thread in the forum was started after 2008 show ADVERTISEMENT C and if the thread was started before 2008 just show ADVERTISEMENT A.

AND,

For all other user groups, show ADVERTISEMENT B as above if thread in the forum was started before 2009, and if the thread was started after that show ADVERTISEMENT D.

I have tried the snippet below, but it is not working as I am getting both sizes of ads showing no matter what the thread start date is or the usergroup is....

<!-- MAIN FORUM TAG MEMBERS -->
<if condition="$forumid == '14'">
<if condition=" in_array($bbuserinfo[usergroupid],array(30,9))">
<if condition="$dateline > '1230768000'">
ADVERTISMENT A LEADERBOARD
<else />
ADVERTISEMENT C LEADERBOARD
</if>
</if>
</if>
<!-- MAIN FORUM TAG GUESTS -->
<if condition="$forumid == '14'">
<if condition=" in_array($bbuserinfo[usergroupid],array(2,3,4,5,6,7,8))">
<if condition="$dateline < '1230768000'">
ADVERTISMENTS B 3 BOXES
<else />
ADVERTISEMENTS D 3 BOXES
</if>
</if>
</if>

What am I doing wrong here? Can someone point me in the right direction? Thanks.