The City of Toronto will be doing work on the Unwin St Bridge from Wed May 29 @ 8:00 pm until sometime on Fri May 31.  Construction will take place overnight, and during this time the bridge will be subject to closures. Vehicles will be allowed to cross every 15-20 minutes.  The cycle path will remain open. Link to Toronto Construction Notice.

Also note that the Cherry St bridge is still closed, the city has not yet announced when this bridge will be available for traffic. Details about the closure can be found here.