Further info on Ns1Provider shared_notifylist usage

CHANGELOG.md

@@ -4,6 +4,14 @@
 
 * NS1 NA target now includes `SX` and `UM`. If `NA` continent is in use in
   dynamic records care must be taken to upgrade/downgrade to v0.9.13.
+* Ns1Provider now supports a new parameter, shared_notifylist, which results in
+  all dynamic record monitors using a shared notify list named 'octoDNS NS1
+  Notify List'. Only newly created record values will use the shared notify
+  list. It should be safe to enable this functionality, but existing records
+  will not be converted. Note: Once this option is enabled downgrades to
+  previous versions of octoDNS are discouraged and may result in undefined
+  behavior and broken records. See https://github.com/octodns/octodns/pull/749
+  for related discussion.
 
 ## v0.9.13 - 2021-07-18 - Processors Alpha
 
@@ -17,7 +25,7 @@
 * Fixes NS1 provider's geotarget limitation of using `NA` continent. Now, when
   `NA` is used in geos it considers **all** the countries of `North America`
   insted of just `us-east`, `us-west` and `us-central` regions
-* `SX' & 'UM` country support added to NS1Provider, not yet in the North 
+* `SX' & 'UM` country support added to NS1Provider, not yet in the North
    America list for backwards compatibility reasons. They will be added in the
    next releaser.
 

octodns/provider/ns1.py

@@ -236,7 +236,8 @@ class Ns1Provider(BaseProvider):
         # Optional. Default: false. true is Recommended, but not the default
         # for backwards compatibility reasons. If true, all NS1 monitors will
         # use a shared notify list rather than one per record & value
-        # combination.
+        # combination. See CHANGELOG for more information before enabling this
+        # behavior.
         shared_notifylist: false
         # Optional. Default: None. If set, back off in advance to avoid 429s
         # from rate-limiting. Generally this should be set to the number