diff --git a/src/main.cpp b/src/main.cpp
index 04d404e..46e26a4 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -247,14 +247,14 @@ static uint16_t read_u16_le(const uint8_t *src) {
 
 static uint32_t compute_batch_rx_timeout_ms(uint16_t total_len, uint8_t chunk_count) {
   if (total_len == 0 || chunk_count == 0) {
-    return 2000;
+    return 10000;
   }
   size_t max_chunk_payload = total_len > BATCH_CHUNK_PAYLOAD ? BATCH_CHUNK_PAYLOAD : total_len;
   size_t payload_len = BATCH_HEADER_SIZE + max_chunk_payload;
   size_t packet_len = 5 + payload_len + 2;
-  uint32_t airtime_ms = lora_airtime_ms(packet_len);
-  uint32_t timeout_ms = airtime_ms + BATCH_RX_MARGIN_MS;
-  return timeout_ms < 500 ? 500 : timeout_ms;
+  uint32_t per_chunk_toa_ms = lora_airtime_ms(packet_len);
+  uint32_t timeout_ms = static_cast<uint32_t>(chunk_count) * per_chunk_toa_ms + BATCH_RX_MARGIN_MS;
+  return timeout_ms < 10000 ? 10000 : timeout_ms;
 }
 
 static bool inject_batch_meta(String &json, int16_t rssi_dbm, float snr_db, uint32_t rx_ts_utc) {