From the version 0.0.7.0, Midrub has the option to set an interval time for the scheduling posts. By default the interval time is 5 seconds between one account and other account where will be published a post.
You can add your wanted interval in Admin Panel -> Settings -> Advanced -> Scheduling interval between accounts. 60 seconds means 1 minute. 3600 = 1 hour.
Same option will work for scheduled RSS’s posts and RSS Feeds Posts.
Please remember to increase even the option max_execution_time in php.