The updates needed warning or reminder emails depend upon the Notification preferences configured in your Ally instance. There's a setting under Admin > Notifications > Check-in Rhythm > Change Schedule > Do not include OKRs and Projects updated within the last x days.
When this is not enabled, Ally will send check-in reminders and display in-app alerts asking to make a check-in irrespective of the last check-in that was made.
Example: If an OKR's progress was updated 2 days ago and when this setting is not enabled, you will receive alerts asking you to update these OKRs. If you configure this and set "Do not include OKRs and Projects updated within the last 5 days", the OKR updated 2 days ago will be excluded from the reminders/alerts.
Upon modifying these settings, select “When saving, apply this schedule to teams” setting if you want the same to change for all the team's objectives checkin reminders.
You can read more about check-in reminders here.