Cloudpools - change in filepool policy

I have a couple of questions. 

Suppose I have a folder structure like so:
/ifs/data/accesszone1/depts/dept1
/ifs/data/accesszone1/depts/dept2
/ifs/data/accesszone1/depts/dept3
Of which I have a file policy that is if the path matches those and last access >3 years which results in the data being moved to the cloud (AWS if it matters).

1. Rather than having three policies (done initially to gauge impact and prevent a huge amount of data from being pushed "all at once"), I wish to reduce the policies down to one, where the path matches /ifs/data/accesszone1/depts. Should I create the new policy and allow it to evaluate/remediate that, then delete the original policies or delete the original policies and create the new?  Does it matter?
2. Following the same scenario but add encryption (where the original is not encrypted).  What is the impact to adding encryption to the new policy where the old policy doesn't have that option set.

Thanks in advance for any input.

Mike