diff --git a/src/ast/seq_decl_plugin.h b/src/ast/seq_decl_plugin.h
index 03cab284a..78ad6d544 100644
--- a/src/ast/seq_decl_plugin.h
+++ b/src/ast/seq_decl_plugin.h
@@ -636,6 +636,7 @@ public:
     }
 
     family_id get_family_id() const { return m_fid; }
+    family_id get_char_family_id() const { return ch.get_family_id(); }
 };
 
 inline std::ostream& operator<<(std::ostream& out, seq_util::rex::pp const & p) { return p.display(out); }
diff --git a/src/ast/sls/sls_context.cpp b/src/ast/sls/sls_context.cpp
index 25700126b..4e40fd13d 100644
--- a/src/ast/sls/sls_context.cpp
+++ b/src/ast/sls/sls_context.cpp
@@ -72,7 +72,7 @@ namespace sls {
             register_plugin(alloc(array_plugin, *this));
         else if (fid == datatype_util(m).get_family_id())
             register_plugin(alloc(datatype_plugin, *this));
-        else if (fid == seq_util(m).get_family_id())
+        else if (fid == seq_util(m).get_family_id() || fid == seq_util(m).get_char_family_id())
             register_plugin(alloc(seq_plugin, *this));
         else
             verbose_stream() << "did not find plugin for " << fid << "\n";
diff --git a/src/ast/sls/sls_seq_plugin.cpp b/src/ast/sls/sls_seq_plugin.cpp
index 8313d22de..70d639965 100644
--- a/src/ast/sls/sls_seq_plugin.cpp
+++ b/src/ast/sls/sls_seq_plugin.cpp
@@ -116,7 +116,7 @@ namespace sls {
     {
         m_fid = seq.get_family_id();
         sls_params p(c.get_params());
-        m_str_update_strategy = p.str_update_strategy() == 0 ? EDIT_CHAR : EDIT_SUBSTR;
+        m_str_update_strategy = (edit_distance_strategy)p.str_update_strategy();
     }
     
     void seq_plugin::propagate_literal(sat::literal lit) {
@@ -681,11 +681,17 @@ namespace sls {
         return d[n][m];
     }
 
-    void seq_plugin::add_edit_updates(ptr_vector<expr> const& w, zstring const& val, zstring const& val_other, uint_set const& chars) {
+    void seq_plugin::add_edit_updates(ptr_vector<expr> const& w, zstring const& val, zstring const& val_other, uint_set const& chars, unsigned diff) {
         if (m_str_update_strategy == EDIT_CHAR)
             add_char_edit_updates(w, val, val_other, chars);
-        else
+        else if (m_str_update_strategy == EDIT_SUBSTR)
             add_substr_edit_updates(w, val, val_other, chars);
+        else {
+            if (diff < 3)
+                add_char_edit_updates(w, val, val_other, chars);
+            else
+                add_substr_edit_updates(w, val, val_other, chars);
+        }
     }
 
     void seq_plugin::add_substr_edit_updates(ptr_vector<expr> const& w, zstring const& val, zstring const& val_other, uint_set const& chars) {
@@ -1012,6 +1018,9 @@ namespace sls {
                 b_chars.insert(ch);
             b += strval0(y);
         }
+
+        // std::cout << "Repair down " << mk_pp(eq, m) << ": \"" << a << "\" = \"" << b << "\"" << std::endl;
+
         if (a == b)
             return update(eq->get_arg(0), a) && update(eq->get_arg(1), b);    
 
@@ -1019,8 +1028,8 @@ namespace sls {
 
         //verbose_stream() << "solve: " << diff << " " << a << " " << b << "\n";
 
-        add_edit_updates(L, a, b, b_chars);
-        add_edit_updates(R, b, a, a_chars);
+        add_edit_updates(L, a, b, b_chars, diff);
+        add_edit_updates(R, b, a, a_chars, diff);
 
         for (auto& [x, s, score] : m_str_updates) {
             a.reset();
@@ -1577,9 +1586,9 @@ namespace sls {
         for (auto ch : value0) 
             chars.insert(ch);
 
-        add_edit_updates(es, value, value0, chars);
-
         unsigned diff = edit_distance(value, value0);
+        add_edit_updates(es, value, value0, chars, diff);
+
         for (auto& [x, s, score] : m_str_updates) {
             value.reset();
             for (auto z : es) {
diff --git a/src/ast/sls/sls_seq_plugin.h b/src/ast/sls/sls_seq_plugin.h
index 7c7fc16ff..ae53cc3ac 100644
--- a/src/ast/sls/sls_seq_plugin.h
+++ b/src/ast/sls/sls_seq_plugin.h
@@ -43,8 +43,9 @@ namespace sls {
         };
 
         enum edit_distance_strategy {
-            EDIT_CHAR,
-            EDIT_SUBSTR,
+            EDIT_CHAR = 0,
+            EDIT_SUBSTR = 1,
+            EDIT_COMBINED = 2,
         };
 
         seq_util seq;
@@ -127,7 +128,7 @@ namespace sls {
         void init_string_instance(ptr_vector<expr> const& es, string_instance& a);
         unsigned edit_distance_with_updates(string_instance const& a, string_instance const& b);
         unsigned edit_distance(zstring const& a, zstring const& b);
-        void add_edit_updates(ptr_vector<expr> const& w, zstring const& val, zstring const& val_other, uint_set const& chars);
+        void add_edit_updates(ptr_vector<expr> const& w, zstring const& val, zstring const& val_other, uint_set const& chars, unsigned diff);
         void add_char_edit_updates(ptr_vector<expr> const& w, zstring const& val, zstring const& val_other, uint_set const& chars);
         void add_substr_edit_updates(ptr_vector<expr> const& w, zstring const& val, zstring const& val_other, uint_set const& chars);
 
diff --git a/src/params/sls_params.pyg b/src/params/sls_params.pyg
index 7ac16479e..1c7c0e0e5 100644
--- a/src/params/sls_params.pyg
+++ b/src/params/sls_params.pyg
@@ -29,5 +29,5 @@ def_module_params('sls',
                         ('bv_use_top_level_assertions', BOOL, True, 'use top-level assertions for BV lookahead solver'),
                         ('bv_use_lookahead', BOOL, True, 'use lookahead solver for BV'),
                         ('bv_allow_rotation', BOOL, True, 'allow model rotation when repairing literal assignment'),
-                        ('str_update_strategy', UINT, 1, 'string update candidate selection: 0 - single character based update, 1 - subsequence based update')
+                        ('str_update_strategy', UINT, 2, 'string update candidate selection: 0 - single character based update, 1 - subsequence based update, 2 - combined')
               ))