We did CPT on a 241 in Oct 2005, out J back F.

We booked right on the 350 day window and still had to be flexible with dates. After I had booked I kept an eye online and there were a few dates available, but they were few and far between and went v.quickly.

The day flight back from CPT seemed to have the better availability. We took this to maximise the non-sleeping F experience, unfortunately it was a poor flight, below average food and a crew that needed semtex to get them out of the galley. In contrast the J out was BA at it's best.

As mentioned above, do be v.careful how you trigger the voucher, the anniversary date is key and inflexible if you mess up.

I'm with Steady-EDI, all my 241's have been triggered by the statement in which you hit the £10k (not the day you hit the magic number) and they reliably arrive in the post 3-5 days post statement.