Fully aware of that. We are talking *only* about being eligible for single line reporting in Nielsen Audio Ratings Reports.
The WFAN simulcast is listed as "WFAN-FM" in Nielsen Audio ratings reports.
If the simulcast was broken for more than 33.6 hours in a 4-week survey period,
the stations would be listed separately in ratings reports as "WFAN-AM" and "WFAN-FM".
Before the 95% rule went in to effect for the February 2019 PPM survey period,
one example had affected Chicago-area simulcast stations WBBM 780 and WCFS 105.9 for the 2015 Chicago Cubs baseball season.
While the Cubs games were broadcast on WBBM, WCFS continued with the all-news format.
Typically WBBM-AM would show with ~4 to ~5 shares and WCFS-FM would show with ~2 shares during the 2015 season.
(Cubs broadcasts shifted to WSCR 670 when White Sox broadcasts went from The Score to WLS 890 for the 2016 season.)
InsideRadio.com article:
Nielsen Audio New Total Line Policy - Feb. 2019