diff --git a/lib/router/group_request.go b/lib/router/group_request.go
index a38956c..4d9db21 100644
--- a/lib/router/group_request.go
+++ b/lib/router/group_request.go
@@ -8,6 +8,7 @@ import (
 	"lab.pztrn.name/fat0troll/i2_bot/lib/dbmapping"
 	"math/rand"
 	"regexp"
+	"strconv"
 )
 
 func (r *Router) routeGroupRequest(update *tgbotapi.Update, playerRaw *dbmapping.Player, chatRaw *dbmapping.Chat) string {
@@ -24,6 +25,11 @@ func (r *Router) routeGroupRequest(update *tgbotapi.Update, playerRaw *dbmapping
 		return squadHandled
 	}
 
+	bastionChatID, _ := strconv.ParseInt(c.Cfg.SpecialChats.BastionID, 10, 64)
+	if update.Message.Chat.ID == bastionChatID {
+		c.Squader.FilterBastion(update)
+	}
+
 	// Welcomes
 	if update.Message.NewChatMembers != nil {
 		newUsers := *update.Message.NewChatMembers
diff --git a/lib/squader/squader.go b/lib/squader/squader.go
index fed3ae4..62eb01f 100644
--- a/lib/squader/squader.go
+++ b/lib/squader/squader.go
@@ -594,3 +594,29 @@ func (s *Squader) ProtectBastion(update *tgbotapi.Update, newUser *tgbotapi.User
 
 	return "ok"
 }
+
+// FilterBastion kicks already joined user if he changed league
+func (s *Squader) FilterBastion(update *tgbotapi.Update) string {
+	user := update.Message.From
+	chatRaw, ok := c.Chatter.GetOrCreateChat(update)
+	if !ok {
+		return "fail"
+	}
+
+	playerRaw, playerOK := c.Users.GetOrCreatePlayer(update.Message.From.ID)
+	if !playerOK {
+		s.kickUserFromSquadChat(user, &chatRaw)
+		return "fail"
+	}
+	_, profileOK := c.Users.GetProfile(playerRaw.ID)
+	if !profileOK {
+		s.kickUserFromSquadChat(user, &chatRaw)
+		return "fail"
+	}
+	if playerRaw.LeagueID != 1 {
+		s.kickUserFromSquadChat(user, &chatRaw)
+		return "fail"
+	}
+
+	return "ok"
+}
diff --git a/lib/squader/squaderinterface/squaderinterface.go b/lib/squader/squaderinterface/squaderinterface.go
index c27dec5..55df281 100644
--- a/lib/squader/squaderinterface/squaderinterface.go
+++ b/lib/squader/squaderinterface/squaderinterface.go
@@ -28,4 +28,5 @@ type SquaderInterface interface {
 
 	ProcessMessage(update *tgbotapi.Update, chatRaw *dbmapping.Chat) string
 	ProtectBastion(update *tgbotapi.Update, newUser *tgbotapi.User) string
+	FilterBastion(update *tgbotapi.Update) string
 }