A deployment can be withdrawn from live execution on real-time data at any time. This will remove it from strategies executors on Signals' server farm and it will not generate further signals.
Once a deployed strategy version has been published, it is available to other users. Undeploying it will automatically unpublish it, causing it to be removed from the Strategies Marketplace. Anyone who had been following the strategy (whether the author or anyone who followed it through the marketplace) will no longer receive trading signals.
An undeployed strategy cannot be re-deployed directly. It must be deployed from a backtest detail, so you must return to your backtests or perform a new one and deploy it from there.