diff --git a/reunion/dist/reunion.cfg b/reunion/dist/reunion.cfg
index 88feed4..1072f03 100644
--- a/reunion/dist/reunion.cfg
+++ b/reunion/dist/reunion.cfg
@@ -85,8 +85,9 @@ cid_SXEI = 1
 # Authorization protocols version. All steamdid's of non-steams players will be changed in common with this value.
 #	1: DProto (deprecated)
 #	2: Reunion 2015-2018
-#	3: Reunion new (recommended)
-AuthVersion = 3
+#	3: Reunion 2018-2024
+#	4: Reunion new (recommended)
+AuthVersion = 4
 
 # SteamIdHashSalt (string)
 # Salt string for SteamIDs hashing. Irreversibly changes SteamIDs. Prevents SteamID stealing.
diff --git a/reunion/src/reunion_authorizers.cpp b/reunion/src/reunion_authorizers.cpp
index 557740a..a035a35 100644
--- a/reunion/src/reunion_authorizers.cpp
+++ b/reunion/src/reunion_authorizers.cpp
@@ -48,14 +48,23 @@ static uint32_t revHash(const char* str, int n = -1)
 	return hash;
 }
 
-// deprecated auth version reunion2015 has a truncated ticket buffer
 size_t Reunion_AuthKeyMaxLen(authdata_t* authdata)
 {
-	const uint32_t MAX_RAWAUTHDATA_TRUNCATED = 16;
-	uint32_t authKeyMaxLen = (g_ReunionConfig->getAuthVersion() == av_reunion2015)
-		? min(authdata->authKeyLen, MAX_RAWAUTHDATA_TRUNCATED) : authdata->authKeyLen;
+	// deprecated auth version reunion2015/reunion2018 has a truncated ticket buffer
+	const uint32_t MAX_RAWAUTHDATA_2015_TRUNCATED = 16;
+	const uint32_t MAX_RAWAUTHDATA_2018_TRUNCATED = 31;
 
-	return authKeyMaxLen;
+	switch (g_ReunionConfig->getAuthVersion())
+	{
+	case av_reunion2015:
+		return min(authdata->authKeyLen, MAX_RAWAUTHDATA_2015_TRUNCATED);
+	case av_reunion2018:
+		return min(authdata->authKeyLen, MAX_RAWAUTHDATA_2018_TRUNCATED);
+	default:
+		break;
+	}
+
+	return authdata->authKeyLen;
 }
 
 void RevEmuFinishAuthorization(authdata_t* authdata, const char* authStr, size_t authKeyMaxLen, bool stripSpecialChars)
diff --git a/reunion/src/reunion_cfg.cpp b/reunion/src/reunion_cfg.cpp
index ad50d36..3b6257a 100644
--- a/reunion/src/reunion_cfg.cpp
+++ b/reunion/src/reunion_cfg.cpp
@@ -271,7 +271,7 @@ bool CReunionConfig::parseCfgParam()
 
 		REU_CFG_PARSE_INT("LoggingMode", m_LogMode, int, rl_none, (rl_console|rl_logfile))
 
-		REU_CFG_PARSE_INT("AuthVersion", m_AuthVersion, auth_version, av_dproto, av_reunion2018)
+		REU_CFG_PARSE_INT("AuthVersion", m_AuthVersion, auth_version, av_dproto, av_reunion2024)
 		REU_CFG_PARSE_INT("ServerInfoAnswerType", m_ServerAnswerType, server_answer_type, sat_source, sat_hybrid)
 
 		REU_CFG_PARSE_BOOL("SC2009_RevCompatMode", m_bSC2009RevEmuCompat)
diff --git a/reunion/src/reunion_player.cpp b/reunion/src/reunion_player.cpp
index cafe83d..f4802a8 100644
--- a/reunion/src/reunion_player.cpp
+++ b/reunion/src/reunion_player.cpp
@@ -52,7 +52,7 @@ void CReunionPlayer::authenticated(int proto, client_id_kind idkind, client_auth
 	const client_id_gen_opts_t* idByIpGenOpts = g_ReunionConfig->getIdByIpGenOpts();
 
 	// use auth key type prefixes
-	bool akPrefixes = g_ReunionConfig->getAuthVersion() == av_reunion2018;
+	bool akPrefixes = g_ReunionConfig->getAuthVersion() >= av_reunion2018;
 
 	switch (m_IdKind) {
 	case CI_REAL_STEAM:
diff --git a/reunion/src/reunion_shared.h b/reunion/src/reunion_shared.h
index d9a41f5..1fe1c42 100644
--- a/reunion/src/reunion_shared.h
+++ b/reunion/src/reunion_shared.h
@@ -70,7 +70,8 @@ enum reuinon_log_mode {
 enum auth_version {
 	av_dproto = 1,
 	av_reunion2015 = 2,
-	av_reunion2018 = 3
+	av_reunion2018 = 3,
+	av_reunion2024 = 4
 };
 
 enum server_answer_type {