Datatables Editor PHP SendGrid Email on MYSQL DB Event Change

I have a fully working Datatables (PHP/MYSQL) example application that will send an email using SendGrid V2 PHP upon creating an new work order record. I need the script modified so it will email users when the activity, or due date fields are modified. Details/Workflow- There is a users table (see [login to view URL]) that stores the email the application sends to. There is a requests table that stores the work orders (see [login to view URL]) and the users assigned. Once a new work order is created (see [login to view URL]) the array of users in "Users Assigned" automatically get emailed using a preCreate function (see [login to view URL] and [login to view URL]). That is all working fine. I now need the emails to generate to the users in the array any time the activities , or due date fields are modified in the application. I believe this can be accomplished using a postEdit function in the [login to view URL] (see [login to view URL]). The second thing I need done is to switch the application so it works with SendGrid V3. Right now it uses the folder Sendgrid (V2) in the root of the project. I need it to use the vendor/sendgrid (v3) folder. V3 handles sending an array of emails slightly different. All of the working code for your review is at [login to view URL] You will need to get an API key at https://sendgrid.com. They are free for testing.