Doubt with implementing Achievements for Google Play.

I am trying to implement Google play services plugin and had few doubts.

1. Since they advice to use PlayGamesPlatform.Instance.IncrementAc$$anonymous$$evement to increment ac$$anonymous$$evement where step count is int, I was wondering how would I pass a float progress. For example, one ac$$anonymous$$evement unlocks when I collect 15 item. Here after collecting one item, step count will be 6.66.

2. How does the local copy of ac$$anonymous$$evements update after incrementing or unlocking any ac$$anonymous$$evement? Do they update automatically or should I have to call LoadAc$$anonymous$$evements again ? I am guessing calling it again might lead to performance issues.

   I am just implementing the logic right now but will only get to test it later therefore came here to look for answers.