The short answer to this is that the itinerary link that you sent to your clients will stay active forever, so long as you Safari Portal account is active and in good standing.
Having said that, in some cases, this might not be ideal - especially if the trip falls through or is cancelled. If you want to deactivate an Itinerary, Guest Portal, or Lookbook, please follow the steps below:
It's generally best practice to manually deactivate the links within Safari Portal. You can do this by:
1. Navigating to the proposal that you want to deactivate within your Itineraries Dashboard.
2. Click on the 3 dots next to the proposal.
3. Click Deactivate Link.
And just like that, your client will no longer have access to this proposal using the link that you had shared with them.
P.S. If you ever want to reactivate it again, simply click those three dots again and select Activate Link.