COTA's wiki is in a bad need of updating and here's what i know. I am trying to contact COTA to get more information and verify what i know
ALL 1999 Novabus LFS and 2001 New FLyer D40LF buses are retired (this is obvious but not mentioned that all are retired in the wiki)
all 2003 New Flyer D40LF buses except 2308 and 2310 are retired. The current status of 2308 and 2310 is unknown but they may have been retired with the order of 2016 Gillig Advantage CNG buses.
2004 New Flyer D40LF Buses: 2403 and 2404 are retired The current status of 2401, 2402, and 2405 is unknown but they may have b