diff --git a/README.md b/README.md
index 63bc437..062d795 100644
--- a/README.md
+++ b/README.md
@@ -82,17 +82,6 @@ for rec in list_exports():       # sorted by (time, group_id)
     print(rec['time'], rec['group_id'], rec['title'], len(rec['members']), 'members')
 ```
 
-If you have data written under the older `run:<time>:<group_id>` or
-`run:<group_id>:<time>` keys, migrate it once:
-
-```bash
-python migrate_run_keys_to_group_time.py --dry-run
-python migrate_run_keys_to_group_time.py
-```
-
-After verifying compare/history output, run it again with `--delete-old` to
-remove the older `run:*:*` keys. Existing `group:<group_id>:<time>` keys are kept.
-
 ## Rate limits and visibility notes
 
 - Telegram limits how fast you can fetch participants; large groups may take longer.
diff --git a/migrate_run_keys_to_group_time.py b/migrate_run_keys_to_group_time.py
deleted file mode 100644
index d1c930b..0000000
--- a/migrate_run_keys_to_group_time.py
+++ /dev/null
@@ -1,129 +0,0 @@
-"""Migrate Redis export keys from run:*:* to group:<group_id>:<time>.
-
-Supported source formats:
-    run:<time>:<group_id>
-    run:<group_id>:<time>
-"""
-
-import argparse
-import os
-
-import redis
-from dotenv import load_dotenv
-
-PREFIX = 'telegram-export'
-TIME_LENGTH = 14
-
-
-def redis_key(*parts):
-    return ':'.join([PREFIX, *parts])
-
-
-def parse_args():
-    parser = argparse.ArgumentParser(
-        description='Migrate Redis export run keys to group key format.',
-    )
-    parser.add_argument(
-        '--dry-run',
-        action='store_true',
-        help='Print planned changes without writing Redis.',
-    )
-    parser.add_argument(
-        '--overwrite',
-        action='store_true',
-        help='Overwrite new-format keys when they already exist.',
-    )
-    parser.add_argument(
-        '--delete-old',
-        action='store_true',
-        help='Delete old run:*:* keys after successful copy.',
-    )
-    return parser.parse_args()
-
-
-def connect_redis():
-    load_dotenv()
-    redis_url = os.getenv('REDIS_URL')
-    if not redis_url:
-        raise SystemExit('REDIS_URL not set in .env')
-    return redis.from_url(redis_url, decode_responses=True)
-
-
-def is_run_time(value):
-    return len(value) == TIME_LENGTH and value.isdigit()
-
-
-def export_key_parts(export_key):
-    parts = export_key.split(':')
-    if len(parts) != 4:
-        return None
-
-    _, key_type, first, second = parts
-    if key_type != 'run':
-        return None
-    if is_run_time(first) and not is_run_time(second):
-        return second, first
-    if not is_run_time(first) and is_run_time(second):
-        return first, second
-    return None
-
-
-def migrate_export_key(client, old_key, args):
-    key_parts = export_key_parts(old_key)
-    if key_parts is None:
-        return 'skipped'
-
-    group_id, run_time = key_parts
-    new_key = redis_key('group', group_id, run_time)
-
-    value = client.get(old_key)
-    if value is None:
-        return 'missing'
-
-    if client.exists(new_key) and not args.overwrite:
-        if args.delete_old and not args.dry_run:
-            client.delete(old_key)
-            print(f'deleted old existing: {old_key}')
-            return 'deleted'
-        print(f'skip existing: {new_key}')
-        return 'skipped'
-
-    print(f'{old_key} -> {new_key}')
-    if args.dry_run:
-        return 'planned'
-
-    client.set(new_key, value)
-    if args.delete_old:
-        client.delete(old_key)
-    return 'migrated'
-
-
-def migrate_run_key(client, old_key, args):
-    """Compatibility wrapper for older imports/tests."""
-    return migrate_export_key(client, old_key, args)
-
-
-def main():
-    args = parse_args()
-    client = connect_redis()
-    counts = {'planned': 0, 'migrated': 0, 'deleted': 0, 'skipped': 0, 'missing': 0}
-
-    for old_key in client.scan_iter(match=redis_key('run', '*', '*')):
-        result = migrate_export_key(client, old_key, args)
-        counts[result] += 1
-
-    print('')
-    print(
-        'exports: '
-        f'{counts["migrated"]} migrated, '
-        f'{counts["deleted"]} deleted, '
-        f'{counts["planned"]} planned, '
-        f'{counts["skipped"]} skipped, '
-        f'{counts["missing"]} missing'
-    )
-    if args.dry_run:
-        print('dry run only; no Redis keys changed.')
-
-
-if __name__ == '__main__':
-    raise SystemExit(main())