[Bug] date_picker_group does not sync initial period on first page load

[MarjoCo]

1. Is it related to Long Term Statistics (LTS)?

No

1a. If it is related to Long Term Statistics (LTS) then please attach your CSV file(s) of entities

I didn't

2. Your YAML Code

type: custom:statistics-graph-chart-card
card_header: 🌡️ Outdoor Temperature
x_grid_style: dashed
y_grid_style: dashed
show_date_picker: true
date_picker_group: ecowitt
date_picker_default_mode: month
group_by: hour
entities:
  - entity: sensor.gw3000a_outdoor_temperature
    name: Outdoor Temperature
    color: "#f87171"
    show_in_legend: true
    show_range_band: true
    tap_action:
      action: more-info
  - entity: sensor.gw3000a_feels_like_temperature
    name: Feels Like
    color: "#fb923c"
    show_in_legend: true
    show_range_band: true
    tap_action:
      action: more-info
annotations: []
date_picker_initial_period: month
stat_types:
  - mean
  - min
  - max

3. Bug Description

When using date_picker_group with multiple cards and date_picker_default_mode: month set on one card, only that specific card loads in the correct period on first page load. All other cards in the group default to day view. After manually clicking the period button once, all cards sync correctly and the group works as expected on subsequent interactions.
Expected behavior: All cards in the same date_picker_group should respect the date_picker_default_mode and load in the same period on initial page load — not just after the first manual interaction.
Workaround: Adding date_picker_default_mode: month to every card in the group individually fixes the issue on first load, but defeats the purpose of date_picker_group.

picture with workaround on windchill & dewpoint card, rest without month default setting: