From 11:45 p.m. tomorrow (Friday, October 21) to 5:00 a.m. Monday, October 24 there will be no 4 or 5 trains running in either direction at Borough Hall. Use 2, 3, A, C, R, or (late night) N trains as options.
The following work week (Monday, October 24 to Friday, October 28) each night from 11:45 p.m. to 5:00 a..m there will be no service in either direction at Court street or on the R/N platforms at Borough Hall. Use the 4 as an option. On these same nights from 10:00 p.m. to 5:00 a.m. F trains in both directions will be diverted to the A/C line, which means no service in either direction at the York Street station in DUMBO. Use the High Street station as an option.
For planned service changes that may affect travel on other parts of the system, either during the weekend or the following week, see MTA Info or The Weekender.