Segments of the Red Line will shut down early on seven nights in July to give workers more time for slow zone-related maintenance, and the Green Line faces a bevy of disruptions next month, MBTA officials announced Thursday.

The T rolled out its latest monthly schedule of service changes, which in addition to substantial impacts on the Red and Green Lines features changes to the Orange Line and the commuter rail's Kingston, Middleborough, Greenbush and Worcester Lines.

Starting around 8:45 p.m. each night from July 11-13 and again on July 20, shuttle buses will replace trains between JFK/UMass and North Quincy Stations on the Red Line. Buses will also replace trains between JFK/UMass and Braintree Stations starting around 8:45 p.m. from July 21-23.

Crews plan to "perform critical rail and tie replacement work that will alleviate speed restrictions" during those diversions, a T official said. MBTA data show about 24 percent of all Red Line tracks cannot safely support full-speed train travel.

In addition to a 12-day closure of the Green Line's B Branch from July 17-28, T officials on Thursday announced the single-stop Union Square branch that opened as part of the Green Line Extension will shutter for more than a month.

Trains will not run between Lechmere and Union Square Stations from July 18 to Aug. 28 due to "critical repair work by MassDOT on the Squire Bridge, which crosses over tracks near Union Square Station," the MBTA said. Riders in the area will be asked to use several MBTA buses, including the Route 86, Route 87 and Route 91.

All four of the Green Line's branches will feature some degree of closure on the weekend of July 15-16 while crews "perform comprehensive inspections of the structural, electrical, mechanical, and fire, life, and safety systems of the sub-surface Green Line tunnel."

Another round of downtown Boston subway closures will also hit in late July and early August related to the ongoing Government Center Garage demolition by HYM Construction, a private developer. From July 29 to Aug. 9, Orange Line trains will bypass Haymarket Station and Green Line service will be suspended between North Station and Government Center. The MBTA suggested riders walk between affected stops in the area, though "accessibility vans" will be available on demand by speaking to T workers.

On the commuter rail's Kingston, Middleborough and Greenbush Lines, shuttle buses will replace trains between South Station and Braintree after 7:30 p.m. on July 10-14, July 17-21 and July 22-23. Framingham/Worcester Line trains will also be replaced by shuttle buses between Worcester and Grafton Stations on July 29 and 30.

"The MBTA apologizes for the inconvenience of these scheduled service changes, and appreciates the understanding and patience of riders as this critical and necessary work to maintain, upgrade, and modernize the system takes place," officials wrote in a press release summarizing the changes.