We have new Joomla installation with Joomla 3.8.5 with PayPlans latest version 3.6.3 and Jomsocial 4.5.
We are currently in the setup process.
We have installed and enabled Micro-subscription under Configuration Advanced settings
There is information that this will enable to sell subscription based on minutes and that timer with minute and second field
will appear on plan edit screen.
I checked but this is not the case.