A minor data point..
- booked a fully qualifying BAH to Tenerife (flights and 8 says hotel) many moons ago for travel in late Sept.
- in between booked a hire car and am sure in the process it asked if wanted to add to an existing booking.
- added the PNR for the original booking in the expectation that should there be a problem with the flights a cancellation would cover all elements (including the later booked car).
- it was only after going through the booking process it dawned on me.. "have I disqualified the original (qualifying) booking by adding something after the original booking" ...?

But yesterday, 8th working day after return, the Double TPs landed safely in both OH and my accounts