Getting onto SiSi is easier than it seems. You do not need to download the full client every time.
The client will not update automatically. You need to carry out the following steps.
Duplicate EVE Online CLient
Amend the info.plist with relevant commands at SiSi Commands
Startup SiSi client
Allow update to complete.
Re-enter info.plist commands again as the update trashes them.
Copy that info.plist to the desktop for future use.
When you receive the cannot update message do the following:
Trash the current SiSi client.
Duplicate your EVE Onine client.
Open Package Contents.
Open the Contents folder.
Open the 'info.plist' file in TextEdit
In the <dict> section, ADD the following key and string from the webpage SiSi Commands
<string>eve.exe /end /server:18.104.22.168</string>
Save and close the info.plist file.
Duplicate info.plist to the desktop for future easy access.
Start the client. It will then ask you to update. Once that is completed. Quit the application and go back into the SiSi package contents and trash the info.plist. Replace with the one on the desktop.
Keep a copy of the Sisi prefs for when the server is updated again and you get the cannot access message.