[SOLVED] How to change project planned end date

Thanks!
I have created the resource and allocated resources to their projects. I have also assigned the resource to activity, but I don't get how to set the monthly planned hours for each resource. Please advice, thanks!
Here are the activities that I created. I'm thinking about creating one activity for each month and set the start date to the 1 st day of the month.


And then the planning part.

Hi,

I did the recalculate planning. I don't understand why it became red for the first activity. The rate is 57% of 80 hours work is about 18 days, it should exceed one month.



This resource has another project simultaneously with a rate of 43% and it shows green.


It's been driven me nuts! Please help! Thanks!

Thanks! I know that's why it is red but I don't know how it is calculated, why it is planned after the validated end date. When I calculate myself it shouldn't exceed the validated end date.
My calculation is based on the resource rate and assigned hours. For example the task 1.1.1. The resource has a rate of 57% with assigned 80 hours of work, so the calculated duration would be 80/(8*0.57)/5=3.5 weeks, which is less than one month as planned. Is there another constraint I should consider? Please correct me if I'm wrong.