For three consecutive weekends starting on the weekend of February 15, 2020, the TTC was short turning the 501 Queen service west of Humber Loop at Kipling Loop. This is being done to allow the City of Toronto to do some work on the sidewalk on Lake Shore Blvd. W. at Long Branch Loop.
Here are some pictures from today:

#4450 departing Kipling Loop

#4517 in Kipling Loop

#4517 departing Kipling Loop while #4456 enters Kipling Loop

#4486 departs Kipling Loop as #4461 pulls into Kipling Loop

#4571 pulling into Kipling Loop

#4486 turning onto Lake Shore Blvd. W.

#4571 turning onto Lake Shore Blvd. W.

#4456 turns off Kipling Ave. and onto Lake Shore Blvd. W.

#4456 turns into Kipling Loop

#4571 on Kipling Loop prior to entering Kipling Loop

#4462 turning onto Kipling Ave.

#4461 on Kipling Ave. prior to entering Kipling Loop
And now for a video of some action at Kipling Loop as the streetcars head towards the loop, enter and depart the loop, and head back onto the Lake Shore: