Loki returns data for last 11 minutes but now for 12

Question

I have loki running in container together with grafana and promtail. My docker-compose.yaml

version: "3"

networks:
  loki:
    driver: bridge
    ipam:
      config: 
        - subnet: 192.180.2.0/24

services:
  loki:
    image: grafana/loki:2.8.6
    container_name: loki
    volumes:
      - ./loki-config.yaml:/etc/loki/loki-config.yaml
      - /etc/localtime:/etc/localtime:ro
      - /data:/tmp
    command: -config.file=/etc/loki/loki-config.yaml
    ports:
      - "3100:3100"
    networks:
      - loki
    logging:
      driver: "json-file"
      options:
        max-size: 1m
        max-file: "3"
        tag: "common.logging.loki.docker"

  promtail:
    image: grafana/promtail:2.4.2
    container_name: promtail
    restart: always
    volumes:
      - /var/lib/docker/:/var/lib/docker:ro 
      - /var/log:/var/log
      - ./promtail-local-config.yaml:/etc/promtail/config.yaml:ro
      - /etc/localtime:/etc/localtime:ro
    command: -config.file=/etc/promtail/config.yaml
    networks:
      - loki
    ports:
      - "1514:1514/tcp"
      - "9080:9080/tcp"
    logging:
      driver: "json-file"
      options:
        max-size: 1m
        max-file: "3"
        tag: "common.logging.promtail.docker"

  grafana:
    image: grafana/grafana:10.2.0
    container_name: grafana
    restart: always
    environment:
      - GF_DATAPROXY_TIMEOUT=1200
      - GF_DATAPROXY_KEEP_ALIVE_SECONDS=300
      - GF_LOG_LEVEL=debug
    ports:
      - "3000:3000"
    networks:
      - loki
    volumes:
      - /etc/localtime:/etc/localtime:ro
      - /opt/grafana_data:/var/lib/grafana
      - /opt/grafana_etc:/etc/grafana
    logging:
      driver: "json-file"
      options:
        max-size: 1m
        max-file: "3"
        tag: "common.logging.grafana.docker"

auth_enabled: false

server:
  http_listen_port: 3100

schema_config:
  configs:
    - from: 2020-10-24
      store: boltdb-shipper
      object_store: filesystem
      schema: v12
      index:
        prefix: index_
        period: 24h

common:
  path_prefix: /tmp/loki
  storage:
    filesystem:
      chunks_directory: /tmp/loki/chunks
      rules_directory: /tmp/loki/rules

  replication_factor: 1
  ring:
    kvstore:
      store: inmemory

limits_config:
  split_queries_by_interval: 15m
  max_entries_limit_per_query: 15000

query_range:
  # make queries more cache-able by aligning them with their step intervals
  align_queries_with_step: true
  max_retries: 5
  parallelise_shardable_queries: true
  cache_results: true


ruler:
  storage:
    type: local
    local:
      directory: /tmp/rules

I'm able to query logs. I run a first query to get logs for last 5 minutes. I get nice resposne with 4200 log lines processed in .2s Quiery inspector I have gotten responses for 6 minutes, 7 minutes sometimes 11 and 12 when there was not so much logs yet incoming. But going further the query goes on for some time and then I get Error: net/http: request canceled (Client.Timeout exceeded while awaiting headers) What could be a problem?