I had been tracking a Philly to Rome and return from Venice late September for some time, as AA/BA had this in the upper 700s end of last year, but my partner was not yet ready to pull the trigger and it disappeared.
Lo and behold - as I kept playing with it, I noticed some movement in this (if one excluded Venice and round-tripped Rome), and this afternoon there were Lufthansa combos that almost worked.
I came back up after dinner, and suddenly that AA/BA combo was there for $570! Booked. I had to go back in and check something about 90 minutes later - and this same flight now costs over a grands. Well. it did say on the AA site "only 3 seats left" when I grabbed it.Must have been a small bucket of seats. FWIW, there were two options out of Philly, one BA via Heathrow the other AA transfer to Iberia in Madrid. That second option was only available at the low price via Iberia, that combo on AA was over a grand also when I booked.