Hi Srini,
Does the URL of the "Rate Plan Detail" page have some unique parts, such as query string parameter names? In this case you can mix them with wildcards to uniquely identify this page.
For example, if the page URL is:
http://example.com/rate-plan-detail?planname=KingRateyou can use
Sys.browser("iexplore").Page("*rate-plan-detail*")
or
Sys.browser("iexplore").Page("*?planname=*")
or something like that.