"There Can't Be A General Election This Year"?

They would just ignore the Fixed Term Parliaments Act. What would anyone do? Why would anyone want to do anything?

If the Queen dissolves Parliament, then she dissolves Parliament. And if the Prime Minister "asked" her to do so, then she would do it.

"The Act removes the Royal Prerogative"? Try it.

If the Prime Minister is determined to have a General Election, then the Prime Minister will have a General Election.