diff --git a/core/archipelago/src/mesh/listener/mod.rs b/core/archipelago/src/mesh/listener/mod.rs
index 0e3c7f02..f486968d 100644
--- a/core/archipelago/src/mesh/listener/mod.rs
+++ b/core/archipelago/src/mesh/listener/mod.rs
@@ -87,6 +87,18 @@ const RECONNECT_DELAY_INIT: Duration = Duration::from_secs(5);
 /// Maximum reconnect delay (cap for exponential backoff).
 const RECONNECT_DELAY_MAX: Duration = Duration::from_secs(60);
 
+/// Minimum time a session must run before we trust it enough to reset
+/// backoff to the minimum. Without this gate, a device that connects then
+/// fails again within a couple of seconds (e.g. mid-boot-loop) never backs
+/// off — every retry immediately re-opens the port, which toggles DTR/RTS
+/// (resets many ESP32 boards' MCU on native-USB and CP2102/CH340
+/// auto-reset-circuit boards alike), turning a device that's merely
+/// unstable into a self-sustaining boot loop that outlasts whatever
+/// triggered the original instability. Confirmed live 2026-07-23: a Heltec
+/// V3 stuck retrying every ~5-15s for 5+ minutes after a failed firmware
+/// flash left it in a marginal state.
+const STABLE_SESSION_THRESHOLD: Duration = Duration::from_secs(20);
+
 /// Number of consecutive write failures before we consider the device dead
 /// and trigger a reconnection cycle.
 const MAX_CONSECUTIVE_WRITE_FAILURES: u32 = 3;
@@ -560,6 +572,7 @@ pub fn spawn_mesh_listener(
                 return;
             }
 
+            let session_start = std::time::Instant::now();
             match session::run_mesh_session(
                 &state,
                 &data_dir,
@@ -582,13 +595,14 @@ pub fn spawn_mesh_listener(
             {
                 Ok(()) => {
                     info!("Mesh session ended cleanly");
-                    // Session was established before ending — reset backoff
-                    reconnect_delay = RECONNECT_DELAY_INIT;
+                    // Only trust a session that actually ran for a while —
+                    // see STABLE_SESSION_THRESHOLD's doc comment.
+                    if session_start.elapsed() >= STABLE_SESSION_THRESHOLD {
+                        reconnect_delay = RECONNECT_DELAY_INIT;
+                    }
                 }
                 Err(e) => {
-                    // Check if session was ever connected (vs failed to open)
-                    let was_connected = state.status.read().await.device_connected;
-                    if was_connected {
+                    if session_start.elapsed() >= STABLE_SESSION_THRESHOLD {
                         reconnect_delay = RECONNECT_DELAY_INIT;
                     }
                     error!("Mesh session error: {} (retry in {:?})", e, reconnect_delay);