Reflex: Delaying events based on a behavior

Using reflex-frp and reflex-dom I need to delay events based on a behavior. I have:

delayEvent :: (MonadWidget t m, Reflex t) 
           => Event t () -> Behavior t NominalDiffTime -> m (Event t ())
delayEvent e b = switch . current <$> widgetHold (return never) eDelsM
  where
    eDelsM = (`delay` e) <$> b <@ e -- Event t (m (Event t ()))

however the return event never fires. Is there a simple mistake I'm making here or does the whole approach need rethinking?

Apparently, the delay will never fire because when the widget defined by eDelsM is active from event e0, it will be waiting until the next event, e1 to create a delay. However, by the time the next instance of the event fires, e1, a new instance of the eDelsM widget will become active and start waiting for the next instance of the event, e2. The solution is to trigger a new event as soon as eDelsM is recreated.

eDelsM = (\t -> getPostBuild >>= delay t) <$> b <@ e