Fix release process feature freeze info

Author: bukka

docs/release-process.md

@@ -27,7 +27,7 @@ GA release date). The pre-release cycle consists of at least:
 - 3 beta releases
 - 4 release candidates
 
-Feature freeze for the next major/minor occurs with the first beta release.
+Feature freeze for the next major/minor occurs with the first RC release.
 
 We refer to alpha, beta, and RC as *non-stable releases*, while GA are *stable*.
 
@@ -871,17 +871,28 @@ If you choose to create a patch-level release, follow these steps:
    mailinglist.
 
 
+## RFC voting deadline
+
+For any RFCs to be included in the new release, they should be discussed and
+have their voting polls closed no later than when the first beta is released.
+However, this does not mean the new feature must have a complete implementation
+by this date. It needs to be implemented before the feature freeze though.
+
+As a courtesy to the community, the release managers should remind others about
+this deadline by posting reminders to [email protected] at 5 weeks and 3
+weeks prior to the first beta release. Those intervals are chosen because the
+RFC needs to be announced at least 4 weeks before the deadline and the voting
+needs to start at least 2 weeks before this deadline. The messages should
+include this information.
+
 ## Feature freeze
 
-A major/minor version [feature freeze][] occurs with the first beta release.
-Specifically, it occurs when the first beta release is packaged, which means the
-feature freeze occurs two days before the first beta release.
+A major/minor version [feature freeze][] occurs with the first RC release.
+Specifically, it occurs when the first RC release is packaged, which means the
+feature freeze occurs two days before the first RC release.
 
 The feature freeze for `php-src` means that we will not accept any new features
-after the date of the feature freeze. For any RFCs to be included in the new
-version, they should be discussed and have the voting polls closed no later than
-the feature freeze date. However, this does not mean the new feature must have a
-complete implementation by this date.
+after the date of the feature freeze.
 
 Following the feature freeze, the focus of work for the new version will be on
 fixing bugs, writing tests, and completing/polishing all accepted features.