He really did change then as a full time cheerleader for Cruz, and very stealthily dissed Trump (often dishonestly) every chance he got.
I remember him doing that against Newt in 2012, but it was only necessary for less than a week. Newt never recovered, it was the so called conservative media that was trashing Newt, then Rush piled on, and Newt wasn't strong enough to withstand the heat.
“I haven’t been able to listen to Rush since late February. It just disturbed me too much. I have stopped at least until he finally comes to his senses. I will never quite fully trust him again.”
Rush has always been very savvy about Republican primaries. He’s famous for never choosing sides, or favoring one candidate over another, until the nominee is decided. I don’t know what possessed him to abandon that workable modus operandi in this primary, but he did - and it’s going to cost him. Dearly.
The loss of trust is the real biggie. Many of his Trump supporting listeners will never return, after his ill treatment of them these last couple of months. I doubt enough of us will tune out to kill his show, but I’ll bet it’ll be a measurable percentage.