diff --git a/doc/org-manual.org b/doc/org-manual.org
index 4466af8e4..5217e647d 100644
--- a/doc/org-manual.org
+++ b/doc/org-manual.org
@@ -8792,7 +8792,9 @@ a ~day~, ~week~, ~month~ or ~year~.  For weekly agendas, the default
 is to start on the previous Monday (see
 ~org-agenda-start-on-weekday~).  You can also set the start date using
 a date shift: =(setq org-agenda-start-day "+10d")= starts the agenda
-ten days from today in the future.
+ten days from today in the future.  ~org-agenda-start-on-weekday~
+takes precedence over ~org-agenda-start-day~ in weekly and bi-weekly
+agendas.
 
 Remote editing from the agenda buffer means, for example, that you can
 change the dates of deadlines and appointments from the agenda buffer.
diff --git a/lisp/org-agenda.el b/lisp/org-agenda.el
index 87517d041..7f3794e01 100644
--- a/lisp/org-agenda.el
+++ b/lisp/org-agenda.el
@@ -1184,7 +1184,9 @@ Custom commands can set this variable in the options section."
   "Non-nil means start the overview always on the specified weekday.
 0 denotes Sunday, 1 denotes Monday, etc.
 When nil, always start on the current day.
-Custom commands can set this variable in the options section."
+Custom commands can set this variable in the options section.
+
+This variable only applies when agenda spans either 7 or 14 days."
   :group 'org-agenda-daily/weekly
   :type '(choice (const :tag "Today" nil)
 		 (integer :tag "Weekday No.")))
@@ -4359,7 +4361,10 @@ This check for agenda markers in all agenda buffers currently active."
 Custom commands can set this variable in the options section.
 This is usually a string like \"2007-11-01\", \"+2d\" or any other
 input allowed when reading a date through the Org calendar.
-See the docstring of `org-read-date' for details.")
+See the docstring of `org-read-date' for details.
+
+This variable has no effect when `org-agenda-start-on-weekday' is set
+and agenda spans 7 or 14 days.")
 (defvar org-starting-day nil) ; local variable in the agenda buffer
 (defvar org-arg-loc nil) ; local variable