'Delay until' finish time of 'Queue a new build' not working in Azure Logic App - azure

Question

I'm triggering an Azure Logic App from an https webhook for a docker image in Azure Container Registry.
The workflow is roughly:
When a HTTP request is received
Queue a new build
Delay until
FinishTime of Queue a new build
See: Workflow image
The Delay until action doesn't work in that the queueried FinishTime is 0001-01-01T00:00:00.
It complains about the wrong format, so I manually added a Z after the FinishTime keyword.
Now the time stamp is in the right format, however, the timestamp 0001-01-01T00:00:00Z obviously doesn't make sense and subsequent steps are executed without delay.
Anything that I am missing?
edit: Queue a new build queues an Azure pipeline build. I.e. the FinishTime property comes from the pipeline.

Answer 1

You need to set a timestamp in future, the timestamp 0001-01-01T00:00:00Z you set to the "Delay until" action is not a future time. If you set a timestamp as 2020-04-02T07:30:00Z, the "Delay until" action will take effect.
Update:
I don't think the "Delay until" can do what you expect, but maybe you can refer to the operations below. Just add a "Condition" action to judge if the FinishTime is greater than current time.
The expression in the "Condition" is:
sub(ticks(variables('FinishTime')), ticks(utcNow()))
In a word, if the FinishTime is greater than current time --> do the "Delay until" aciton. If the FinishTime is less than current time --> do anything else which you want.(By the way you need to pay attention to the time zone of your timestamp, maybe you need to convert all of the time zone to UTC)

Answer 2

I've been in touch with an Azure support engineer, who has confirmed that the Delay until action should work as I intended to use it, however, that the FinishTime property will not hold a value that I can use.
In the meantime, I have found a workaround, where I'm using some logic and quite a few additional steps. Inconvenient but at least it does what I want.
Here are the most important steps that are executed after the workflow gets triggered from a webhook (docker base image update in Azure Container Registry).
Essentially, I'm initializing the following variables and queing a new build:
buildStatusCompleted: String value containing the target value completed
jarsBuildStatus: String value containing the initial value notStarted
jarsBuildResult: String value containing the default value failed
Then, I'm using an Until action to monitor when the jarsBuildStatus's value is switching to completed.
In the Until action, I'm repeating the following steps until jarsBuildStatus changes its value to buildStatusCompleted:
Delay for 15 seconds
HTTP request to Azure DevOps build, authenticating with personal access token
Parse JSON body of previous raw HTTP output for status and result keywords
Set jarsBuildStatus = status
After breaking out of the Until action (loop), the jarsBuildResult is set to the parsed result.
All these steps are part of a larger build orchestration workflow, where I'm repeating the given steps multiple times for several different Azure DevOps build pipelines.
The final action in the workflow is sending all the status, result and other relevant data as a build summary to Azure DevOps.
To me, this is only a workaround and I'll leave this question open to see if others have suggestions as well or in case the Azure support engineers can give more insight into the Delay until action.
Here's an image of the final workflow (at least, the part where I implemented the Delay until action):
edit: Turns out, I can simplify the workflow because there's a dedicated Azure DevOps action in the Logic App called Send an HTTP request to Azure DevOps, which omits the need for manual authentication (Azure support engineer pointed this out).
The workflow now looks like this:
That is, I can query the build status directly and set the jarsBuildStatus as
#{body('Send_an_HTTP_request_to_Azure_DevOps:_jar''s')['status']}
The code snippet above is automagically converted to a value for the Set variable action. Thus, no need to use an additional Parse JSON action.