Looks like at least a few customers have had problems with the bird deterrent slipping and blocking the wind channel.
Suggestion - a small “lip” just above the wind channel (even just a few mm) would keep this from happening.
Alternate Suggestion - a few “pins” round the edge of the unit which could mate with slots in the deterrent.
If you are suggesting a change to the plastic molding, I would take it one step further and suggest that ears/holes for the bird spikes be included in the upper case without needing to use the bird deterrent band. For that matter, adding the metal spikes to the Tempest kit for people to optionally use would be nice and probably not a significant increase in per unit manufacturing cost…