diff --git a/README-airt.md b/README-airt.md
index e2ee76ae..4f78b94b 100644
--- a/README-airt.md
+++ b/README-airt.md
@@ -85,7 +85,7 @@ install gr-iqtlabs
 $ git clone https://github.com/google/flatbuffers -b v23.5.26
 $ git clone https://github.com/nlohmann/json -b v3.11.2
 $ git clone https://github.com/deepsig/libsigmf -b v1.0.2
-$ git clone https://github.com/iqtlabs/gr-iqtlabs -b 1.0.40
+$ git clone https://github.com/iqtlabs/gr-iqtlabs -b 1.0.42
 $ mkdir -p flatbuffers/build && cd flatbuffers/build && cmake -DCMAKE_INSTALL_PREFIX=~/.conda/envs/$CONDA_DEFAULT_ENV .. && make -j $(nproc) && make install && cd ../..
 $ mkdir -p json/build && cd json/build && cmake -DCMAKE_INSTALL_PREFIX=~/.conda/envs/$CONDA_DEFAULT_ENV .. && make -j $(nproc) && make install && cd ../..
 $ mkdir -p libsigmf/build && cd libsigmf/build && cmake -DUSE_SYSTEM_JSON=ON -DUSE_SYSTEM_FLATBUFFERS=ON -DCMAKE_INSTALL_PREFIX=~/.conda/envs/$CONDA_DEFAULT_ENV -DCMAKE_CXX_FLAGS="-I $HOME/.conda/envs/$CONDA_DEFAULT_ENV/include" .. && make -j $(nproc) && make install && cd ../..
@@ -116,7 +116,6 @@ $ LD_PRELOAD=$HOME/.conda/envs/$CONDA_DEFAULT_ENV/lib/libgomp.so.1 gamutrf-scan
 gamutrf-scan will repeatedly print
 
 ```
-gr::log :ERROR: source0 - soapy: ignoring unknown command key 'tag'
 gr::log :DEBUG: retune_fft0 - rx_freq: {}
 gr::log :DEBUG: retune_fft0 - new rx_freq tag: {}, last {}
 gr::log :DEBUG: retune_fft0 - retuning to {}
diff --git a/docker/Dockerfile.base b/docker/Dockerfile.base
index e2477b5b..713a3cd8 100644
--- a/docker/Dockerfile.base
+++ b/docker/Dockerfile.base
@@ -87,7 +87,7 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
   libvulkan-dev \
   python3-numpy
 WORKDIR /root
-RUN git clone https://github.com/iqtlabs/gr-iqtlabs -b 1.0.41
+RUN git clone https://github.com/iqtlabs/gr-iqtlabs -b 1.0.42
 COPY --from=iqtlabs/gamutrf-vkfft:latest /root /root/gr-iqtlabs
 WORKDIR /root/gr-iqtlabs/build
 COPY --from=sigmf-builder /usr/local /usr/local
diff --git a/gamutrf/grscan.py b/gamutrf/grscan.py
index 63c3d9ed..dfdec266 100644
--- a/gamutrf/grscan.py
+++ b/gamutrf/grscan.py
@@ -60,6 +60,7 @@ def __init__(
         vkfft=False,
         wavelearner=None,
         write_samples=0,
+        tag_now=False,
     ):
         gr.top_block.__init__(self, "scan", catch_exceptions=True)
 
@@ -74,6 +75,7 @@ def __init__(
         self.iqtlabs = iqtlabs
         self.samp_rate = samp_rate
         self.retune_pre_fft = None
+        self.tag_now = tag_now
 
         ##################################################
         # Blocks
@@ -166,6 +168,7 @@ def __init__(
             description,
             rotate_secs,
             False,
+            self.tag_now,
         )
         self.fft_blocks.append(retune_fft)
         zmq_addr = f"tcp://{logaddr}:{logport}"
@@ -358,6 +361,7 @@ def get_fft_blocks(
                 tune_step_fft,
                 skip_tune_step,
                 tuning_ranges,
+                self.tag_now,
             )
         else:
             self.retune_pre_fft = blocks.stream_to_vector(
diff --git a/gamutrf/scan.py b/gamutrf/scan.py
index 111d4368..0d60034e 100644
--- a/gamutrf/scan.py
+++ b/gamutrf/scan.py
@@ -284,6 +284,13 @@ def argument_parser():
         action=BooleanOptionalAction,
         help="use pretuning",
     )
+    parser.add_argument(
+        "--tag-now",
+        dest="tag_now",
+        default=False,
+        action=BooleanOptionalAction,
+        help="send tag:now command when retuning",
+    )
     return parser