"Summer line-up" means...

"LeGardePourpre;c-17877470" wrote:
Previously ...
"EA Reveals The Sims 3 Line-Up for 2013 Including New Expansion and Stuff Packs"
https://ir.ea.com/press-releases/press-release-details/2013/EA-Reveals-The-Sims-3-Line-Up-for-2013-Including-New-Expansion-and-Stuff-Packs/default.aspx

I think it will be similar. Packs and themes should be announced, it's more detailed than a 6-month Roadmap.

• May : GP10
  
• June : EP11
  
• July : SP19
  
• September : GP11
  

From your Keyboard to Sims-God. That would be such a dream <3