For most large scale apps (web or native) rollouts take multiple hours or even days. Ramps are slow to avoid widespread incidents and allow canary analysis to detect issues.

If you are at that scale then surely you put up some load balancers which can look at the client request (eg a request header `Accept-Version: abc123` or whatever) and route it to the correct backend server that can handle the request.

If you're not at that scale ie if your app deploys in a few seconds then just forcing a reload seems like a perfectly feasible strategy.