Teresaliu

I think ``expired`` is better, because ``completed`` represents this one-off PingSource has fired succeed. And the function of filter out expired PingSource is not implemented yet in original code? I...

@lionelvillard I'm sorry for this PR is pending so long time because of Spring Festival:). The field that one-off PingSource marked I changed to be ``UnExpired``, it represents once this...

> An upgrade is a normal operation, so at least we should be resilient enough to pass upgrades, so I think we should have a way of making the semantic...

> In addition, by validating datatime (on pingsource create actions _only_) is expired already or not we are sure that there won't be a pingsource created for a datetime in...

> Sounds good to use completed status and have the runner communicate when it is completed @pierDipi I've added it, you could review if anytime you be free

@pierDipi Thanks for @evankanderson's review, and I think we need to be consistent with knative spec, ``Succeeded`` is better, and when we use cron PingSource, the status is set to...