action: target_timeframes.update_target_timeframe_config failing to allocate slots after upgrade to 1.5.1

[ragg987]

Describe the bug

This is a new problem that seems to be related to the to the v1.5.1 update. action: had behaved well prior to this update.

I've just retested this after rolling back to 1.5.0 and the issue goes away. I'm currently using this rolled-back version to avoid this bug.

Reproduction steps

update the sensor through the action:. I've checked and my IOG rates are updating correctly. Example:

action: target_timeframes.update_target_timeframe_config
data:
  target_hours: 3
  target_weighting: ""
  target_offset: ""
target:
  entity_id: >-
    binary_sensor.target_timeframes_octopus_energy_import_myclimate_intelligent_heating

Resulting in:

icon: mdi:camera-timer
friendly_name: myclimate_intelligent_heating (octopus_energy_import)
end_time: 19:30
find_highest_values: false
hours: 3
hours_mode: exact_hours
kind: target_rate
latest_values: false
name: myclimate_intelligent_heating
rolling_target: false
start_time: 20:00
target_times_evaluation_mode: all_target_times_in_past
type: Continuous
data_source_id: octopus_energy_import
calculate_with_incomplete_data: false
minimum_required_minutes_in_slot: 25
offset: null
weighting: null
target_times: 
target_times_last_evaluated: 2026-04-05T20:26:43.302271+01:00
time_periods_incomplete: true
overall_average_value: 0
overall_min_value: null
overall_max_value: null
current_duration_in_hours: 0
current_average_value: null
current_min_value: null
current_max_value: null
next_time: null
next_duration_in_hours: 0
next_average_value: null
next_min_value: null
next_max_value: null

Expected behaviour

action: should update the sensor entity correctly

Integration Version

1.5.1

Home Assistant Version

2026.4

Fresh Install?

After upgrading

Home Assistant Logs

Sorry - I failed to capture the logs with 1.5.1 test as I had rolled back to 1.5 and restarted HA. Let me know if you cannot reproduce this and i'll re-apply 1.5.1 and capture the logs.

Confirmation

• I confirm that I cannot find my solution within the documentation
• I confirm that I cannot find my solution within the FAQ

[ITistheworst]

I think I am seeing something similar. I use the update action to update a sensor on demand for a use case and then read back the value (ie I am putting an appliance on now, what is the best slot between now and x) but it has been intermittently failing recently. Rolling back version to 1.5.0 does seem to have stopped me from being able to recreate the issue for now.

It seems to be something to do with the timeslot target_start_time being 'close' to the target_end_time, e.g. this was failing:

  domain: target_timeframes
  service: update_target_timeframe_config
  service_data:
    target_start_time: '09:30'
    target_end_time: '09:00'
    target_hours: 3

However, trying:

  domain: target_timeframes
  service: update_target_timeframe_config
  service_data:
    target_start_time: '09:30'
    target_end_time: '10:00'
    target_hours: 3

Worked fine. Potentially some timezone weirdness or something like that?

[Daverover66]

I had the same issue last night. I updated to v1.5.1 two weeks ago and it had been fine until last night when it didn't select any slots whatsoever. I have also rolled back to v1.5.0 until a fix is identified.

Thanks.