Scheduling BOTs and stop once the file available



We have 3 BOTs for executing a process. Before triggering the BOTs we need to check a file availability in mainframes and get the count. Depending on the count in the file we need to split the load to 3 BOTs. So my idea is to schedule a BOT to check for availability with a interval of 15 min. Say for example.starting from 9AM bot should check for file availability and if the file is available it should split the load for remaining 2 BOTs and execute the process. Please let me know if it is possible. If so, if the file is available at 9:00AM or 9:15AM or 9:30AM(Which is scheduled to check every 15 min), it should stop checking for file and process the actual data from mainframe file after sharing the load with other 2 BOTs. Can somebody suggest on this.