Incorrect calculation of new end date when a rolling period membership is renewed to a fixed period membership type

When an existing (current) membership with a "rolling" period type is renewed and the membership type is changed to a type with a fixed period - the new end date is not calculated properly.

EXAMPLE:

• Rolling period membership start date = Nov 6, 2010, end date = Nov 5, 2011 (NOTE: end date does not matter for this flow)
• Renew the membership and select a different membership type belonging to same membership organization. New membership type is fixed period, Jan 1 - Dec 31 with Sept 1 rollover. (renewal happens sometime between Sept 1 and Dec 31 - so is in rollover period).

Calculated end date is Nov 6, 2012 (due to rollover). End date SHOULD BE Dec 31, 2012 since the new membership type has a fixed period.

---- Original Post ----
Start and date for a fixed period membership renewal after a rolling period membership has the wrong start date (using pricesets)

Example Lifetime membership with rolling period (start date = current date, end date = null)
add fixed period membership with Jan 1 start date and Dec 31 end date (1 year)

Start date = lifetime start date rather than Jan 1
end date is one year after start date (correct period) but wrong end date (Dec 31)

Have not been able to verify on demo site due to non-revocerable error in creating a new priceset posted in forum) whether this is becuase of missing end date, pricesets, etc so needs more testing.