Originally Posted by
agehall
I've always thought their protection works by having the inbound carrier take responsibility, ie if BA is late and you miss the connection to AA/US, they expect BA to handle it.
"Protection" is an inaccurate term. If you are on one ticket and BA delivers you late to PHL causing you to misconnect, BA is responsible for rebooking you onward. The key to timing is to figure Plan B. Are you OK with an overnight at PHL? Your backup here is likely on WN at 4:45 (via either ATL or MDW to HOU, not IAH). But, WN does not interline with any other carrier, so it is a cash purchase on the spot.
But, OP is not on one ticket and not connecting. BA's obligation ends at PHL.
As an initial matter, I'm not seeing a US/AA flight to IAH at that time on October 3. Certainly nothing later. Thus, if you no show for your xPHL, you are at a minimum stuck overnight.
AA (not US), had a published policy whereby it would rebook in "disruptions" across OW tickets. However, AA has removed that statement from its website, but leaves it in the back pages for TA's. Whether it remains a consumer-facing policy by October for US flights remains to be seen.