OK, so you had a bus disembarkation arrival, something I didn't spot in your earlier posts, which is a very relevant fact which you need to draw to the attention of BA. It would therefore have been nearly impossible to make that connection, most NCL arrivals are to an airbridge, the level above the bus arrival point and which greatly speeds up the connection process. A bus arrival adds a good 5 or 10 minutes to disembarkation. You made a mistake following the crowd (happens every day!), you should have followed the purple signs for Flight Connections instead, which would take you upstairs to a desk which can help you better.

Presumably someone else from NCL went upstairs, and perhaps made the flight, since that's usually how the comment you saw ends up in the customer relations answers. Still it's a very understandable thing you did and actually not relevant to your claim - at that point you are well below "conformance" of 35 minutes, you missed your flight by being late to arrive and having a bus service rather than an airbridge. By going to landside and presumably up to the check-in area for rebooking, you then made it impossible for conformance to be waived. Either way I would do as I and simons1 have suggested above and clarify the errors in BA's response, and if necessary follow it through to CEDR.
Well it's irrelevant now, but should it happen again, ask for the dispatch details in this thread since we can track the aircraft's operations and thus validate (or not) the rotation issue.

The reasons for delays are available within the first 48 hours on sites such as ExpertFlyer. After that point it's much harder to locate the information required to figure out what happened.

Thanks so much again

Sorry, yes I realised later that I had not made this clear at all!

Is this something they can hold against my claim?

So, the rotation issue is irrelevant to the claim now?

Oh I see, but is this 48hs since...?

I don't believe so, because with best endeavours, no BA status (presumably), checked luggage (presumably) and a child, the chances of Flight Connections ringing up for clearance to let you through are nearly zero. The core facts are that you missed the flight because it was late, and so that is why you need to revert to BA with the shortest possible reply, but mentioning the bus and the fact you were well below "conformance", and inviting them to review their answer or give a CEDR deadlock answer.

Well it should be, we don't have the information on where the rotational delay happened. If it was in Nice 6 hours ago it is totally irrelevant. If something at NCL stopped a swift turnaround then it may be relevant. Perhaps the captain explained something to you at the start of the flight on the PA? Essentially this is a debate about exceptional circumstances, and a rotation delay is not normally exceptional at all, but there may be more details behind this.

....the flight in question, which in your case has long since passed. Hence why it applies for next time.

That's interesting - are you saying that you would have more chances without a child? I would have assumed the opposite!

Ah! got it now!

Thanks again for all your help

I suspect it's about the speed of getting to the gate, which tends to be slower if you have a child. It's very much geared towards not delaying the flight.

Yes, well formally I doubt it's a rule, but to get to a distant gate such as at T5B would take some time, particularly if you were not familiar with the airport and were unable to move too swiftly. Gates close at 20 minutes to departure officially. Had you been a solo Gold card holder (and therefore familiar with T5) with no checked baggage or children they may well have rung up to get clearance. But only from Flight Connections upstairs since that allows you into the rest of the building without doing the security search again. But having gone via those glass doors out to landside, you could only get back in via a security check and time was by this time very much against you, child or no child.

Precisely. I had another look at post #1295 . In dealing with CEDR, i'd appreciate any advice here as to whether it is considered ok to use the case number in that post as further evidence to show precedence? I am writing my reply now to CEDR so we can get the process moving again, now that I have BA's CS admission in writing that the RR engines are the root cause.

I can't see what harm it would do.

I just don't want to find myself on the wrong side of some data breach accusation! Even though the case was clearly posted in FT. I guess if I refer to this forum in my reply, then that explains how I heard about it.

Yeah, makes sense...

Well, that was quick. Here is their reply:

Thanks for your most recent email. I’m sorry to hear you remain unhappy with our resolution to your complaint. I’ve reviewed all of the information you’ve given us, however, our response will not change and we’re unable to respond to any further requests for compensation.
You can refer your complaint to the Centre for Effective Dispute Resolution (CEDR) for an independent decision to be made. [cont]

That was all. They have not answered my question re.th erotation of the aircraft or the 60min figure
Can I just proceed with a claim to CEDR then?

Yes, just have a good think about how to put your claim concisely to CEDR and focusing on key facts, namely the delay with the bus, and rotation not being extraordinary circumstances.

As an update to my posts way further up. I am now mid-process with CEDR (put my case, BA's "defence" has been submitted, I have my response in, Adjudicator due to be appointed tomorrow), for a cancellation with 40 hours notice for long haul 787-800 (ie the Trent-1000 issues). I quoted the relevant CEDR cases on this forum in my response. I was amazed that BA is still not providing any detail whatsoever in their defence on specific steps taken to avoid cancellation on the specific flight. Surely it can't be that hard to show the schedules for all 787s and 777s (even 747s!) on that day?? Are they just hoping we will get bored/exhausted/lose some braincells and accept their halfhearted excuses? They even say in their defence "The Network Operations Planning team had hoped that they would have been able to resource another aircraft to operate the flight from elsewhere in the fleet. However, due to the amount of aircraft impacted by the manufacturing defect this was not possible. At the time of making the decision to cancel the flight [ie 40 hours before departure!] there was not sufficient time to arrange a wet-lease". Nothing like "hoping" that something will turn up! That was as specific as they got. Will continue to keep the forum posted.

I've had the same experience very little detail in the hope you give up. Once you have the detail it's a lot easier to pick up on their failings. Ironically the defence they submitted for my claim actually strengthened my case. It's an enormous waste of money defending a claim that's less than £1k with one of Londons top law firms, who charge out £750 an hour which is what they're doing in my case.