Clockwork Free customers are limited to using 300 timers per month, within their Jira instance. Once the limit is met, there is a 5-day grace period when timers can still be created. After five days, no more timers can be started until the next month.
Timers vs. Worklogs:
A timer is started either automatically via a transition to an active status (if automatic tracking is enabled) or using the “start“ button in the issue view.
When a timer is stopped, a corresponding worklog is created. Worklogs are entries that record the time, and amount of time, an issue was worked on by a given user.
Please Note: that manually created worklogs do not count against the limit and can continue to be created after the limit has been reached.