Seems there is no other way. You have to open all the ports of the firewall when you upload the app. The port shown here may not be consistent.
Here is a snapshot of the communication,
(src ip - dst ip - protocol - src_port > dst_port)
> 10.145.50.51 17.152.249.56 TCP 56358 > 33001
> 10.145.50.51 17.152.249.102 TCP 56373 > 44001
> 10.145.50.51 17.152.19.127 TCP 56369 > https
System and Network Requirements
Application Loader 1.3 requires a minimum OS version of Mac OS X 10.5.3.
Note: Because Application Loader is integrated with Xcode you can also deliver your binary directly from
Xcode. For more information on this delivery mechanism, review the Distributing Applications section in the
iOS Development Guide located in the iOS Dev Center.
The following table lists details about the servers Application Loader uses to deliver your application binary
files to the App Store. For the best upload experience, verify that all of the ports and IP addresses are accessible.
The following table lists details about the servers Application Loader uses to deliver packages and application binary files. For the best upload experience, verify that all of the ports and IP addresses are accessible.
<Server IP Address TCP Port UDP Port>
------- ---------- -------- ---------
itmsdav.apple.com 17.152.19.125 443 n/a
contentdelivery.itunes.apple.com
17.152.19.127 443* n/a
vgr101.apple.com 17.152.249.51 33001 33001-33500
vgr102.apple.com 17.152.249.52 33001 33001-33500
vgr103.apple.com 17.152.249.53 33001 33001-33500
vgr104.apple.com 17.152.249.54 33001 33001-33500
vgr105.apple.com 17.152.249.55 33001 33001-33500
vgr106.apple.com 17.152.249.56 33001 33001-33500
vgr107.apple.com 17.152.249.57 33001 33001-33500
vgr108.apple.com 17.152.249.58 33001 33001-33500
vgr301.apple.com 17.172.190.141 33001 33001-33500
vgr302.apple.com 17.172.190.142 33001 33001-33500
vgr303.apple.com 17.172.190.143 33001 33001-33500
vgr304.apple.com 17.172.190.144 33001 33001-33500
vgr305.apple.com 17.172.190.145 33001 33001-33500
vgr306.apple.com 17.172.190.146 33001 33001-33500
vgr307.apple.com 17.172.190.147 33001 33001-33500
vgr308.apple.com 17.172.190.148 33001 33001-33500
sgr201.apple.com 17.152.249.101 44001 44001-44500
Note: Because Apple periodically releases new versions and updates to its software, servers listed in the table may change mid-release.