Will my activity points go down?
 

As I lose weight and the activity does not require the same effort it did at 285#, will the amount of points for that activity drop?

I think so... I don't know how much the new points plus system takes your current weight into consideration when calculating how many activity points you get, but in the older system as your weight went down so did your points earned for the same amount of exercise.

Yes it will...there is a chart in the materials you get on week 1.