nearby Cameron Beach Yard) and Castro. As a result, there was no need to bring the 1972 portals back into regular use when the F line reopened as a full-time service in 1995. Light rail service briefly used the 1972 portals for two weeks in 1991 (August 19 to September 2), when K-L-M service was diverted via 17th and Church Streets, and entering and leaving the Muni Metro subway via the portal on Duboce Avenue, to permit track work near Castro station. Forest Hill and Eureka Valley stations were originally constructed with low platforms, as streetcars of that era had steps to load passengers from street level. However, the six new Market Street subway stations were built with high-level platforms for speedier level boarding onto the new Boeing LRVs. West Portal station, which was originally a surface stop outside of the tunnel's western entrance, was rebuilt as a high-platform station located just inside of the entrance. With Eureka Valley station permanently closed, Forest Hill was left as the only low-platform station on the Muni Metro subway. Muni soon modified the station with high-level platforms, completing that project in 1985. COVID-19 impact and attempted restart On March 30, 2020, Muni Metro service, including trains through the Twin Peaks Tunnel, were replaced with buses due to the pandemic. Light rail service returned on August 22, with the routes reconfigured to improve reliability in the tunnel and at West Portal. K Ingleside and L Taraval services were interlined, running between and and not entering the tunnel, with passengers transferring at West Portal station. M Ocean View and T Third Street services were interlined, running between and Balboa Park station. Longer S Shuttle services operated in the tunnel. The forced transfers at West Portal were criticized by disability advocates. Service was stopped and substituted with buses just three days later due to a malfunctioning overhead wire splice in the subway and the need to quarantine a control center staff after a COVID-19 case. On May 15, 2021, Muni Metro rail service resumed the K Ingleside, T Third Street, and S Shuttle lines. K Ingleside and T Third Street services were again interlined (as before the August changes). At that time, some stations were converted to new wayfinding signage based on international standards, with compass directions like "westbound" replacing older "inbound"/"outbound" directions. M Ocean View service resumed on August 14. The L Taraval remained as