הזיהויים של jackandshirley

Please Read Before Identifying: I'm asking that you ONLY ID to species if you are extremely familiar with both BCCH and CACH vocalizations and/or have birded extensively in the overlap zone of their ranges. I already know what Merlin Sound identifies these chickadees as; I'm looking for experience-based human opinion. If leaving this observation at genus is the best practice, please let me know and tick the "as good as it can be" box.

When uploading this list to eBird, I found that counting either species would trip the Rare Bird sensor; the common practice at this location seems to be counting any chickadees as Black-capped/Carolina. I'm not sure if this is due to individual practices when submitting lists, or if it's a conscious decision the county reviewers have made. THAT BEING SAID: across the river, in nearby Missouri counties, it seems eBirders regularly count chickadees at species level (which species is more frequently identified (not necessarily present) varies from hotspot to hotspot). With the possibility of hybridization, individual vocal variation, and (most importantly) the fact that each species may learn the song of the other, is it even possible/advisable to ascribe these recording to one or the other? Has there been any new research that contradicts the studies mentioned in the linked article?

Thanks in advance, all who've taken the time to read through these notes!

Audio 1: Started recording at 9:45 AM (Normalized to -3db)
Audio 2: Started recording at 9:52 AM (Normalized to -3db
Audio 3: Started recording at 9:53 AM (Normalized to -3db

Audio 4:: Supercut of other three recordings unedited (other than trimming and fading at the ends of each)