diff --git a/README.md b/README.md
index 0a4b572..7b24325 100644
--- a/README.md
+++ b/README.md
@@ -47,7 +47,7 @@ pip install sourmash_plugin_directsketch
 
 ## Usage Considerations
 
-If you're building large databases (over 20k files), we highly recommend you use batched zipfiles to facilitate restart. If you encounter unexpected failures and are using a single zipfile output (default), `gbsketch`/`urlsketch` will have to re-download and re-sketch all files. If you instead set a batch size using `--batch-size`, e.g. 10000, then `gbsketch`/`urlsketch` can load any batched zips that finished writing, and avoid re-generating those signatures. For `gbsketch`, the batch size represents the number of accessions included in each zip, with all signatures associated with an accession grouped within a single `zip`. For `urlsketch`, the batch size represents the number of total signatures included in each zip. Note that batches will use the `--output` file to build batched filenames, so if you provided `output.zip`, your batches will be `output.1.zip`, `output.2.zip`, etc.
+If you're building large databases (over 20k files), we highly recommend you use batched zipfiles (v0.4+) to facilitate restart. If you encounter unexpected failures and are using a single zipfile output (default), `gbsketch`/`urlsketch` will have to re-download and re-sketch all files. If you instead set a batch size using `--batch-size`, e.g. 10000, then `gbsketch`/`urlsketch` can load any batched zips that finished writing, and avoid re-generating those signatures. For `gbsketch`, the batch size represents the number of accessions included in each zip, with all signatures associated with an accession grouped within a single `zip`. For `urlsketch`, the batch size represents the number of total signatures included in each zip. Note that batches will use the `--output` file to build batched filenames, so if you provided `output.zip`, your batches will be `output.1.zip`, `output.2.zip`, etc.
 
 
 ## Running the commands