Will solar allow me to add new classes tomorrow? As in drop a class and change it to another? And will it allow me to switch the ones I have to a different semester?

You can drop/add courses, and you can also change tutorials/labs/cores.

you are allowed to switch courses to another semester as long as the course does not have any term specification, meaning a certain course can only be done during a specific semester.

As far as I know, every course besides electives have had a term specification ( check out the attachment below). thats just an ENG example.