It seems some integrations are running from a data center in a different region, probably introducing some additional network latency? See HTTP Integration pushes from European Azure server for application on ttn-handler-us-west?
If true, then maybe using the MQTT Data API from one’s own region (and maybe not even using a decoder in TTN Console) might give one the best chance to have a downlink be transmitted in the window of the current uplink?
(While also scheduling the downlink as soon as possible, like by postponing any time consuming file, logging or database operations until after scheduling the downlink, if possible.)