Schedule pipelines using GUI in only middle of the hour

We are going through migrating our triggers from .yml to scheduled pipelines. We have a few pipelines which need to be triggered at 15th min of hour or 30th min of an hour.

Currently, in circleCI GUI, we can select only the hour (i.e., 12:00 or 13:00) but not in minutes (i.e., 12:15 or 13:30). As we have multiple workflows which needs to be tiggered once in a day at 14:15 and one more at 14:30.
How can we do that, is there anything that circleCI is going to release in future ?