You didn't indicate why the Guard advised that you won't upgrade. Was that a budget issue, or an airmanship issue?

Three upgrade attempts in a year? The most glaring problem I see, or the impression given, is one of judgement. Why rush into the checkrides like that, so close together, especially on the heels of not passing the first time? What prep did you take, or seek, for subsequent upgrades?

First of all; the most important thing: it's an airplane. An object. It's a job. Neither one is you; we are not our job. Neither of them are your identity. Neither are they the end of the world. There are a lot of airplanes and a lot of jobs. You can certainly explain your experiences later, but your immediate concern is putting food on the table. You are not a failure. You have had setbacks. You had failed training events, but the only thing this represents is a wake up call.

It's impossible to diagnose what went wrong, but the examiner apparently found multiple issues. Is this the same at the Guard? If so, then there may be an airmanship issue; this is something you need to focus on, and that may or may not be possible where you work now.

If you are able to retain your employment, I suspect that you'll be barred from further upgrade attempts, which means a permanent F/O position there. If that's the case, progression won't be possible, even if employment is, so you'd need to go somewhere else to progress. You need to take a long, hard introspective look at what prevented you upgrading at the Guard, and what led to these training issues. Don't go in for an upgrade if you're not ready. Not the first, nor second, nor especially a third. From your description, it sounds like this would be your first pilot in command experience, or captain experience. You may benefit from falling back to a job where you can be PIC and focus on doing the PIC role.

You will need to put distance between yourself and these events, and two things are required to do that: time, and experience. To make up for any training event failure, the farther in the rear-view mirror the better, but what really makes the past faded and dull is being able to show recent, current experience with a success...you need to establish a history of passing checkrides, and show command experience. Whethe that means finding a job in a Caravan or anything else, at this stage you need to focus on doing whatever you must to fix the problems that exist, and to build and demonstrate experience over time (no way around it) that show you can do the job.

While it may be possible to do a lateral hop over to another regional, you're going to a SIC position on the heels of the upgrade problems. Upgrading isn't about flying the airplane. It's about command. An upgrade checkride shouldn't be any more than what one would encounter on a proficiency check, or in other words, just the basics. The flying shouldn't be the problem, but the command part may be, which is flying and talking and deciding. It's about managing. I would suggest going for an evaluation or a proficiency check in a local flight school training device, like a Redbird, see what they have to say, and take it with an open mind. Before determining how to press on with the career, you need to target all the problem areas and fix those. It sounds like there may be a few.

You may be harder on yourself than those around you, and that won't help you at all. We're all perfectionists by nature, but it's often said that perfect is the enemy of good; we need to do a good job, but we can lose focus by either trying too hard for perfection, or by slapping ourselves for every failure to achieve perfection. Give yourself a break: take a deep breath, get an evaluation, and press on. You might consider buying that check airman a drink and some of his time to sit down after hours and discuss what you need to do, off the record. If you can't pin down that examiner, get someone else who can give good counsel and talk it out. A frank evaluation, no pride on the line, is worth its weight in gold.

Reviewing your comments again, I see you're thinking about going for a direct-entry captain position. You shouldn't have gone for the second and third upgrades, especially so quickly. You're not marketable presently for a legacy or major; it shouldn't even be a consideration, but you really shouldn't be thinking aobut direct-entry captain positions. You just failed three captain upgrades in a row, in short order. Wise up. Don't do that again.

Also...six years at Republic (four, if you were out two years on active)...should be enough time to learn the procedures and the airplane, especially if you're studying all the time in your spare time (as anyone intending to upgrade should do). On the heels of a third upgrade failure, you shouldn't be thinking about your next captain position (direct entry, etc). You should be thinking about establishing a solid track history (won't happen quickly...it requires time), and then making a sensible, calculated upgrade attempt. The training failures go in your pilot record database (PRD) for life. Don't put any more in there. Don't rush to move up. Establish a history of passing checkrides, first, and as already stated, do a very thorough, detailed anlysis of what got you here. These events can be overcome, but the three upgrade attempts show poor judgement in my opinion, especially in such short order, and the drive to go somewhere else right into a command position doesn't show much better judgment. Slow down. Think about this carefully. Get some assistance, a review, and some counseling with your union rep, a check airman, and an interview prep place that can help you begin to think about how to explain these events.

The only real way to explain any training failure is to own it, and to show what you learned from it. The proof comes in a long line of subsequent checkrides.