I work as an engineer at a Gov installation. I took a Temp position to get a rather large boost in pay and it was extended 3 times because they did not want to lose me. I got pushed back to my old position due to a new looming pay system along with all other Temps. However, I had been in this position for well over 18 months. If you are in a Temp for longer than one year, they cannot reduce your pay when returning to your old position. About two months pass, a bunch of HR screw ups and the place I had been working as a Temp hires me permanently full time. I accept the job and am told by HR that they will workout the pay issue once I am brought on board. Keep in mind, my butt NEVER leaves the office where I was a Temp, even after getting pencil whipped back down to my old position and my duties did not decrease, but increased.

I had sent numerous emails, tried calling HR, etc. NEVER got a response. I cc'd my supervisor and our division chief on the emails too so I would have witnesses. Now, 7 months later after our Colonel and GS-15 get involved does this get resolved. I had a paper trail at least an inch thick, documented everything and had developed a timelines of events and had copies of all my personnel records. The result...a check this Friday in excess of $10K with over $6K in back pay and my salary permanently increased by nearly $10K. Best of all, I am now exceeding the same salary I was making back in 2009 in the private sector. That was a long hard crawl.

LESSONS:
Do your due diligence whenever it involves money, property, legal matters, etc. Create a trail via email, snail mail, whatever you have to do to get a record firmly established and note exactly who and when you provided the information. The more details you can provide the better.

Always keep records within the federal government for your protection.
I kept all kinds of my records and of all my employees.
I was a WS15. CYA.