Deprecation Message using output=json&legacy=1?

[c3rberus]

I run the local windows build of freegeoip inside some powershell scripts.

I start the server with:
freegeoip.exe -ArgumentList "-http=:1234 -silent -tcp-fast-open"

I geoip using:
PS C:\Users> Invoke-WebRequest -Uri "http://localhost:1234/json/186.116.207.169?access_key=SOMEKEY&output=json&legacy=1" -UseBasicParsing | Select -Expand Content | ConvertFrom-Json

This returns:

__deprecation_message__ : This API endpoint is deprecated and will stop working on July 1st, 2018. For more information please visit: https://github.com/apilayer/freegeoip#readme
ip                      : 186.116.207.169
country_code            : CO
country_name            : Colombia
region_code             :
region_name             :
city                    :
zip_code                :
time_zone               : America/Bogota
latitude                : 4.5981
longitude               : -74.0758
metro_code              : 0

I am concerned why the deprecation_message message shows up? The local method I am using, will this stop working in the near future? If so, how should I be calling the Invoke-WebRequest to prevent this from happening?

The local version I am using is 3.5.0.