diff --git a/Dockerfile b/Dockerfile
index a6c4fdb..1488954 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -14,6 +14,14 @@ RUN apt-get update && \
     apt-get clean && \
     rm -rf /var/lib/apt/lists/*
 
+# Give IBC more time to detect the login/config dialog on the current headless
+# GCE target. The upstream 60s default has been too short during keepalive
+# recovery and caused intermittent exit code 1112 before the Gateway became
+# API-ready.
+RUN sed -i 's/^LoginDialogDisplayTimeout=60$/LoginDialogDisplayTimeout=180/' \
+    /home/ibgateway/ibc/config.ini \
+    /home/ibgateway/ibc/config.ini.tmpl
+
 COPY --chown=1000:1000 ./container_overrides/run.sh /home/ibgateway/scripts/run.sh
 RUN chmod a+x /home/ibgateway/scripts/run.sh
 
diff --git a/README.md b/README.md
index 6f36017..342d0de 100644
--- a/README.md
+++ b/README.md
@@ -210,6 +210,11 @@ This repository also overrides the upstream headless startup script so Gateway r
 upstream `16bpp` display frequently led to black VNC output and intermittent IBC window
 detection failures before login completed.
 
+The image also raises `LoginDialogDisplayTimeout` from `60` to `180` seconds in both
+`/home/ibgateway/ibc/config.ini` and `config.ini.tmpl`. Keepalive recovery on the current
+GCE target has occasionally needed longer than the upstream default before IBC can detect
+the login/config dialog and drive Gateway back to an API-ready state.
+
 For direct `docker compose` usage outside GitHub Actions, `ACCEPT_API_FROM_IP` must still be set explicitly in `.env`; there is no longer a silent default CIDR.
 
 These GitHub secrets are specific to this repository's deployment flow. They are not intended to be global secrets shared by every quant repository.
diff --git a/tests/test_docker_compose_ports.sh b/tests/test_docker_compose_ports.sh
index 16fddd1..44d7b2e 100644
--- a/tests/test_docker_compose_ports.sh
+++ b/tests/test_docker_compose_ports.sh
@@ -8,6 +8,8 @@ run_override="$repo_dir/container_overrides/run.sh"
 
 grep -Fq 'pip3 install pyotp ib_insync --break-system-packages' "$dockerfile"
 grep -Fq 'FROM gnzsnz/ib-gateway:10.37.1q' "$dockerfile"
+grep -Fq "LoginDialogDisplayTimeout=60$/LoginDialogDisplayTimeout=180" "$dockerfile"
+grep -Fq '/home/ibgateway/ibc/config.ini.tmpl' "$dockerfile"
 grep -Fq 'COPY --chown=1000:1000 ./container_overrides/run.sh /home/ibgateway/scripts/run.sh' "$dockerfile"
 grep -Fq 'chmod a+x /home/ibgateway/scripts/run.sh' "$dockerfile"
 grep -Fq 'libgtk-3-0' "$dockerfile"