Replacement buses that were brought in to ferry riders around during Ottawa's most recent light rail shutdown will be taken off the roads later today, the city says.

The R1 buses will stop running after Tuesday afternoon's rush hour, now that "consistent" service has resumed on the Confederation Line and demand for the buses has declined, transit general manager Renée Amilcar said in a memo to council.

The line was shut down for nearly two months after a train derailed Sept. 19 before entering Tremblay station.

Partial service was restored last Friday and the city had said it hoped to have full service in place by mid-December.

But Allan Hubley, chair of the transit commission, told CBC Tuesday that won't happen. He expects 11 trains to run before Christmas with a return to full service — all 15 trains — in January.

There are currently seven trains on the tracks and a spare is available.

On Tuesday, though, one train was stopped causing reduced service — just over two hours after the memo was released regarding R1 buses. OC Transpo tweeted the train stopped between Lyon and Tunney's Pasture stations. Passengers travelling east had to change trains at Lyon station, the tweet read.

Amilcar's memo also said passenger volumes on the R1 buses have been low since trains started operating again.

Council had adopted a motion to extend the transfer window by a full hour while R1 buses were running, she added, but the return to some semblance of normalcy meant that wouldn't happen right now.

City staff members are still expected to report back to transit commission in 2022 on potentially extending the window permanently to 120 minutes, Amilcar said.