Do development permits expire? This got approved almost two years ago, and if they're signing a new lease with a tenant it sounds like construction isn't beginning any time soon.

Or can they just sit on this indefinitely?

Yes, they can sit on it for a while. It might have to wait until interest rates subside.

Note how the Hudson District was approved circa 2006, but didn’t complete until 2023. Same with Dockside, approved in 2003, touted as complete by 2015, and not even half finished.

Might be a long wait if interest rate drops are the key.

The wording in all of the City of Victoria development permit letters I have seen says "Please note that the Development Permit generally expires two years from the date of council approval unless otherwise specified in the permit." If they haven't started before the two years runs out, I suspect they will have to go back to council to have the DP renewed. But that is much simpler than getting the initial permit.