Workflow return to previous block until action is complete

I have a situation where i want the person receiving an initial form submission to assign someone to the ‘owner’ people column and to send a notification to the initial receiver until an owner is assigned. Once an owner is assigned proceed to the next workflow block.

While we can repeat the previous blocks and actions, it is not possible to know how many times it needs to be repeated. Will the receiver assign an owner on the first reminder, or the fifth reminder?

Currently workflows do now allow an action to return to a previous block, i.e. if ‘Owner’ column is empty, Yes, notify someone, No move to next action. If the answer is Yes, the Owner column is empty, notify them and then return to if ‘Owner’ column is empty after ‘X’ period. This would prevent users guessing how many notifications need to be sent until an action is completed.

Example screenshot below;