I think one of the best examples of this type of confusion is Custer. He is often listed as one of the youngest Generals in the Army and it is often noted that he achieved that rank by being promoted directly from Captain to Brig. Gen shortly before Gettysburg. There is no doubt that just at the week before Gettysburg he was a Captain, but was treated and commanded as a Brigadier General the following week. I don't recall references to him after that point as "Captain Custer" and while Brevet may have been an honorary rank in lieu of other recognition those receiving the rank had no trouble announcing to the world that they were of that rank. Custer would never have announced himself as "Brevet General" and the papers of the day would not have referred to him that way either.
Keep in mind that NOBODY goes to "Honorary" Colonel Sanders Chicken
If you look at his listed dates for rank
here (near the bottom of the Wiki page) you will find the following:
Second Lieutenant, 2nd Cavalry: June 24, 1861
First Lieutenant, 5th Cavalry: July 17, 1862
Captain Staff, Additional Aide-De-Camp: June 5, 1862
Brigadier General, U.S. Volunteers: June 29, 1863
Brevet Major, July 3, 1863 (Battle of Gettysburg, Pennsylvania)
Captain, 5th Cavalry: May 8, 1864
Brevet Lieutenant Colonel: May 11, 1864 (Battle of Yellow Tavern - Combat at Meadow)
Brevet Colonel: September 19, 1864(Battle of Winchester, Virginia)
Brevet Major General, U.S. Volunteers: October 19, 1864 (Battle of Winchester and Fisher's Hill, Virginia)
Brevet Brigadier General, U.S. Army, March 13, 1865 (Battle of Five Forks, Virginia)
Brevet Major General, U.S. Army: March 13, 1865 (The campaign ending in the surrender of the Army of Northern Virginia)
Major General, U.S. Volunteers: April 15, 1865
Mustered out of Volunteer Service: February 1, 1866
Lieutenant Colonel, 7th Cavalry: July 28, 1866 (killed at the Battle of the Little Bighorn, June 25, 1876)
It can a bit confusing to follow all of that so I broke it down into a grid to divide it between US Army regular, US Army Brevet, US Volunteers and US Volunteers Brevet.
Note that he has two listings as Captain in the US Army. One was a an Aide-De-Camp under McClellan and the other was a regular promotion. This would have mean that he would have reverted back to 1st Lt. after McClellan's departure and may have actually gone straight from 1st Lt. in the regular Army to Bvt. Brig. Gen. in the US Volunteers.
A few other interesting things to note:
He was given a Brevet Brigadier General and Brevet Major General on the same day.
He was promoted directly from Regular US Army Captain to Major General with no stops in between.