This loss of protection was new to me...

I was recently flying ABQ-DEN-EWR-EDI

1] On-board at ABQ, pilot comes back and tells us mechanics have been working on issue since 3:30 AM (flight showed "on-time" on everything I looked at).
2] I called 1K desk and asked to be protected on later flight DEN-EWR. She said she did it, but that if I made my original flight, I should call and have the alternate segment canceled.
3] We were able to land S->N at DEN, saving much time. I would now make my original flight.
4] While taxiing to gate, I called, told 1K desk I had made it with time to spare, and they could cancel the later segment. "Thank you, Mr. mauiUAflyer".
5] I get to gate, get in BG 1, go to board. Machine beeps. I've been off-loaded from my original flight! Have to go see gate agent at counter. Now I have no flight to EWR!
6] Get new BP from GA. I hadn't gotten an upgrade, but had a good E+ aisle seat. Now relegated to middle seat in back of bus. UNHAPPY! But at least I'm on my flight to EWR, and will make my connection...
7] Call 1K desk, to express my dismay that I'd followed their directions ,and found myself with no DEN-EWR segment. Nevermind the middle seat.
8] On take-off, emergency braking system activates, as a spare generator faulted. Go and sit in penalty box while brakes cool. Try again, but same fault (at least we weren't at high speed at that time). Excitement I could have lived without.
9] Back to gate. Several de-plane, me as well. Try to get on other flight (my "protected" flight). Door still open, but GA can't process new pax. But then I see my original flight is re-boarding and will depart shortly.
10] Back to old gate. Get back in middle seat, but several in first had been re-booked, so my upgrade came through.
11] Landed EWR with enough time for shower in Club and dinner.

A serious amount of airline sausage-making! All's well that ends well, but it wasn't pretty getting there...