Timeline: past 6 months, not just 3

_layouts/roadmap.html

@@ -39,7 +39,7 @@
                 {%- comment -%}
                 Show the last three complete months
                 {%- endcomment -%}
-                {%- if months_since > 3 -%}
+                {%- if months_since > 6 -%}
                 {%- assign hidden_class = "hidden expand" -%}
                 {%- else -%}
                 {%- assign hidden_class = "" -%}