I am starting an online English school and need your help. I am thinking of buying the plain appointment+ plugin for wordpress to manage the bookings of hours for the students. Through appointment+ the students can select hours on the calendar by availability.And then they can make the checkout and purchase( for each hour the plugin can apply a price).The problem is that I would like to give the students the opportunity to buy a package of 20 hours for example at a lower price respect to the single hours bought.This problem can be resolved with the plugin WP-Members. But now at this point the conditions of expirations have to be different for my needs. The plugin WP-Members makes the package expire only with the condition of expiration dates. I would like that the conditions of expirations for each user who has bought the package of 20 hours are the selections of 20 hours on the calendar instead of the expiration dates.Is it possible to modify some parts of the codes in this plugin to have the results I want? I think the solution is to insert an additional function in the code of the plugin.