Why not head back to LHR from FCO for another 40 tier points and additional miles? You have four Euro segments to use.
If Miles and Tier points are a primary driver I suggest you do a LHR-DXD/MCT/AUH run instead of a flight to FCO. You could pick up a cheap LHR-FCO flight on ba.com for less than GBP90 if you have exact travel dates.
Originally Posted by newbie
3. I can buy and upgrade to club on the BOS-IST round-trip for $892 + 32,5000 miles. Availability of departure dates is wide open. Of course, my return date is in 2007 and thus well outside the booking window. One-way MFUs are too expensive. So my plan is to buy the MFU with a meaningless return date and then change the date when the return date I want becomes bookable (just before using the first leg). I believe I can do this for a $75 change fee and any difference from the original "T" fare. Does this sound right?
You will need to check this out VERY carefully. Some T fares are non-changeable. I am sure I have read somewhere that T fares upgraded with Miles become non-refundable. If I was you I'd post this specific question on the BA Board.