Steps to reproduce:
1) create a Folio Test1
2) create a team member John with two cost rates. First: effective date 2015-01-01 and value 20, second: effective date 2015-03-01 and value 25.
3) create another Folio Test2
4) go to the Team tab and use import data function (key shortcut "i")
5) select "folio to folio" import type
6) import the data from Test1
John after the import is going to have only one cost rate in Folio Test2 with the value of 20 and with effective date set to the current date, so both values are invalid.
Jira 6.3.7, every web browser