I apologize if this is TLDR reply. If so, read until bored – skip the rest.
I won’t guarantee that their answers would be the same, but 12 of my 18 B/C years were worked in a very busy wildland battalion, almost all SRA with only small patches of LRA. About half of it was bordered by Fed land (USFS/BLM) in a patchwork around the lake. These types of fires—single operational period wildland fires were very common - many Type 3 complexity fires were shared with other members here who can chime in as we were often in unified command if we could get away with it. Almost guarantee we would host at least 1 if not a couple of Type 1 fires by the end of the season.
My hope is this might give you some insight into potential answers without being too boring.
1) The IAP. The first in chief was probably or should have been using a ICS 201, or a customized version for their area blended with their CAD system. Their (LFD’s) CAD does a lot of the resource tracking for them, but at least parts of a paper 201 might/should have been used so you can establish DIVS, assignments, and accountability. They caught it at 0436 because that’s what they needed to do, not to avoid writing an IAP, but it’s what they are paid to do - fast aggressive IA. You would only consider a written or formal IAP if the complexity required it, not because of it going into the second day or a subsequent operational period. Since they were able to stop the forward rate of spread it became a moot point. If anything, the 201 would have been added to and that is used as their initial IAP. Remember, an ICS 201 is used until the first IAP is completed. I would bet that if they said they caught it or stopped it at 0436, it was probably contained earlier than that. No chief likes to declare a fire contained or under control only to have to “uncontain it” or admit it’s “off and running” a while later. Also, very unfortunately, current ICS training really messes up what a good IAP should contain in the early stages of an incident. Way overblown in minutia and length.
2) Why did they switch IC’s? This is a fairly common practice in municipal departments when a fire is caught on one shift and another shift is coming on duty. It was probably called because the fire was in a mop-up and reinforcing the line stage so command is passed from one IC to another. During that transition the incoming IC would get a briefing from the off-going IC. Depending on the complexity it could be either done on the fire or maybe at HQ. all the critical elements still need to be discussed. They should review the incident, discuss the 201 and any other notes, and when the on-coming felt comfortable, the off-going would go off-duty. Remember, this was only a few acres, not some giant active firefight. It had been caught and they were performing mop up. If the fire was active and the complexity warranted it, then you might see the original IC keep the fire and the on-coming B/C would take the battalion. Evidently that wasn’t necessary.
3) Where is the ICS 214 that was kept by the 1st IC and what where their passdown notes?
The ICS 214 is used mostly for extended response and when an IAP is developed. Some folks do it as a resource on IA, but during the IA portion its use is not that common. So, it would not surprise me that the resources would not have turned any in. The IC is usually too busy to do an actual 214 on IA, but their comments, pertinent notes, and actions you would find on their 214 would have been recorded on the 201, Section 7, Current and Planned Objectives, Section 8, Current and Planned Actions, Strategies, and Tactics, and the notes area of Section 10, Resources Summary. Also, the ICS 200 Form is still often used by ICs on fires. Heck it is still the most often used form in ICS on initial responses. Many have forgotten its name, the “ruled Yellow Canary Pad.” The ICS 200L is the legal length version - and it does come in white too “200W.”
Hopefully, all of the documents produced have been retained, but in the intervening days when they thought it was all good, they might have been tossed. After all, it was just another IA, and those happen all the time. No one knew at that time what the final result would be. It would be very unfortunate, but it wouldn’t be too surprising from my perspective.
So, those are my potential answers to your questions. There are still many unanswered questions (thankfully you did NOT ask) that throw me for a complete loop from a wildland fire Chief Officer’s perspective.