diff --git a/stew/interval_set.nim b/stew/interval_set.nim
index 38edc33..83c430d 100644
--- a/stew/interval_set.nim
+++ b/stew/interval_set.nim
@@ -779,7 +779,9 @@ proc ge*[P,S](ds: IntervalSetRef[P,S]; minPt: P): IntervalRc[P,S] =
       return ok(Interval[P,S].new(rc.value.left, high(P)))
     return ok(Interval[P,S].new(rc.value))
   if ds.lastHigh:
-    return ok(Interval[P,S].new(high(P),high(P)))
+    const preHigh = high(P) - scalarOne
+    if ds.covered(preHigh,preHigh) == scalarZero:
+      return ok(Interval[P,S].new(high(P),high(P)))
   err()
 
 proc ge*[P,S](ds: IntervalSetRef[P,S]): IntervalRc[P,S] =
@@ -793,13 +795,18 @@ proc le*[P,S](ds: IntervalSetRef[P,S]; maxPt: P): IntervalRc[P,S] =
   if rc.isOk:
     # only the left end of segment [left,right) is guaranteed to be <= maxPt
     if rc.value.right - scalarOne <= maxPt:
-      if high(P) <= maxPt and ds.lastHigh:
-        # Check for fringe case intervals [a,b] gap [high(P),high(P)] <= maxPt
-        if rc.value.right < high(P):
-          return ok(Interval[P,S].new(high(P),high(P)))
-        # Check for fringe case intervals [a,b] + [high(P),high(P)] <= maxPt
+      if ds.lastHigh:
+        if high(P) <= maxPt:
+          # Check for fringe case intervals [a,b] gap [high(P),high(P)] <= maxPt
+          if rc.value.right < high(P):
+            return ok(Interval[P,S].new(high(P),high(P)))
+          # Check for fringe case intervals [a,b] + [high(P),high(P)] <= maxPt
+          if high(P) <= rc.value.right:
+            return ok(Interval[P,S].new(rc.value.left,high(P)))
+        # So maxPt < high(P)
         if high(P) <= rc.value.right:
-          return ok(Interval[P,S].new(rc.value.left,high(P)))
+          # Now `maxPt` is fully within the inner part of `[left,high(P)]`
+          return err()
       return ok(Interval[P,S].new(rc.value))
     # find the next smaller one
     let xc = ds.leftPos.lt(rc.value.key)
diff --git a/tests/test_interval_set.nim b/tests/test_interval_set.nim
index 2cb6e9b..8b50821 100644
--- a/tests/test_interval_set.nim
+++ b/tests/test_interval_set.nim
@@ -177,6 +177,7 @@ suite "IntervalSet: Intervals of FancyPoint entries over FancyScalar":
     check br.total.truncate(uint64) == (uHigh - 10000000) + 1
     check br.verify.isOk
 
+  test "More edge cases detected and fixed":
     br.clear()
     check br.total == 0 and br.chunks == 0
     check br.merge(uHigh,uHigh) == 1
@@ -187,7 +188,6 @@ suite "IntervalSet: Intervals of FancyPoint entries over FancyScalar":
         check ivSet == false
         (ivVal, ivSet) = (iv, true)
       check ivVal == iv(uHigh,uHigh)
-
     block:
       var (ivVal, ivSet) = (iv(0,0), false)
       for iv in br.decreasing:
@@ -200,6 +200,25 @@ suite "IntervalSet: Intervals of FancyPoint entries over FancyScalar":
     check br.merge(1477152,uHigh) == uHigh - 1477151
     check br.merge(1477151,1477151) == 1
 
+    br.clear() # from blockchain snap sync odd behaviour
+    check br.merge(0,uHigh) == 0
+    check br.chunks == 1
+    check br.total == 0
+    check br.ge(1000) == ivError
+    check 0 < br.reduce(99999,uHigh-1)
+    check br.ge(1000) == iv(uHigh,uHigh)
+
+    br.clear()
+    check br.merge(0,uHigh) == 0
+    check br.chunks == 1
+    check br.total == 0
+    check br.le(uHigh) == iv(0,uHigh)
+    check br.le(uHigh-1) == ivError
+    check 0 < br.reduce(99999,uHigh-1)
+    check br.le(uHigh) == iv(uHigh,uHigh)
+    check br.le(uHigh-1) == iv(0,99998)
+    check br.le(uHigh-2) == iv(0,99998)
+
   test "Merge disjunct intervals on 1st set":
     br.clear()
     check br.merge(  0,  99) == 100