Endpoints like /services/haproxy/configuration/frontends/{parent_name}/binds return cached information that's obtained at initialization and never updated (unless disable_inotify is set to false). This means the information could be out-of-date unless Data Plane API is reloaded every time HAproxy configuration file is changed.

Is it possible to add a parameter to enforce re-reading the file when making calls to the affected endpoints?

Worth noticing that /services/haproxy/configuration/raw endpoint is not affected as it always reads the latest on-disk version of the configuration file when handling it.

This can be easily tested by:
0- disable_inotify must be set to true.
1- Perform a GET /services/haproxy/configuration/frontends/{parent_name}/binds. Store the result.
2- Perform a GET /services/haproxy/configuration/raw. Store the result.
3- Manually modify (add/remove) binds in the haproxy.cfg file for {parent_name} frontend.
4- Repeat step (1) and (2). Notice how the result for (1) was the same as before (not reflecting the latest change). (2) do actually show the most recent configuration.