diff --git a/Makefile.inc1 b/Makefile.inc1
--- a/Makefile.inc1
+++ b/Makefile.inc1
@@ -557,7 +557,7 @@
 .endif
 
 .if !defined(PKG_VERSION)
-.if ${_BRANCH:MSTABLE*} || ${_BRANCH:MCURRENT*}
+.if ${_BRANCH:MSTABLE*} || ${_BRANCH:MCURRENT*} || ${_BRANCH:MPRERELEASE*}
 TIMENOW=	%Y%m%d%H%M%S
 EXTRA_REVISION=	.s${TIMENOW:gmtime}
 .elif ${_BRANCH:MALPHA*}
@@ -566,8 +566,6 @@
 EXTRA_REVISION= _${_BRANCH:C/-BETA/.b/}
 .elif ${_BRANCH:MRC*}
 EXTRA_REVISION= _${_BRANCH:C/-RC/.r/}
-.elif ${_BRANCH:MPRERELEASE*}
-EXTRA_REVISION= _${_BRANCH:C/-PRERELEASE/.p/}
 .elif ${_BRANCH:M*-p*}
 EXTRA_REVISION=	_${_BRANCH:C/.*-p([0-9]+$)/\1/}
 .endif