Changing eta documentation (celery#4264)

Author: arpanshah29

docs/internals/worker.rst

@@ -38,9 +38,8 @@ When a message is received it's converted into a
 Tasks with an ETA, or rate-limit are entered into the `timer`,
 messages that can be immediately processed are sent to the execution pool.
 
-ETA and rate-limit are 2 incompatible parameters, and the ETA is overriding
-the rate-limit by default. A task with both will follow its ETA and ignore its
-rate-limit.
+ETA and rate-limit when used together will result in the rate limit being
+observed with the task being scheduled after the ETA.
 
 Timer
 -----

docs/userguide/tasks.rst

@@ -918,10 +918,6 @@ General
     maximum number of  requests per second), you must restrict to a given
     queue.
 
-    .. note::
-
-        This attribute is ignored if the task is requested with an ETA.
-
 .. attribute:: Task.time_limit
 
     The hard time limit, in seconds, for this task.