See the attached 2023 CSX Operating Rules excerpt (Rules C1281-C1298) or follow this link: CSX Chessie Signals (https://signalquiz.com/files/signals/CSX-Chessie-Signals-C1281-C1298-2-1-2023.pdf)
Changes for 2023 are:
C1284 Aspect (b) modified.
C1291 High Signal Aspect (d) added.