Joe Harris, N1QD, writes on the Boston ARC list:
Both the 145.23 and 449.175 repeaters will be in use to support the Boston Marathon all day Monday April 18th. Please defer to event traffic.
Additionally, the 449.175 DMR repeater is currently in “Marathon mode” and will not pass standard NEDECN network traffic until after the event. Please use the Hingham or Danvers repeaters for NEDECN DMR traffic during this time.