The biggest issue with the IT meltdown was NOT the actual IT meltdown itself, not even the cheap overseas outsourcing. The biggest issues were the following:
1) There were dozens of flights ready to go, passengers through security, etc. The problem was that there were few managers senior enough to have any experience in dealing with such an issue as BA had gotten rid of most of them. Even bringing in those off duty was NOT enough. In other words, BA has little to no contingency in place and basically hopes that there will never be IRROPS.
2) Even when these managers were brought in, there were barely any stocks of alternative arrangements, such as boarding cards and stickers, something STANDARD at all outstations, because some idiot had decided not renew any orders for them repeatedly for years as "they were no longer needed" in today's high tech world. Having spent the requisite 10 or 20k over the previous 5 years would have not negated the problem, but could have reduced it significantly.
Now looking at this disaster, it is not the first time that it has snowed in London, it is not the first time that there has been a need for de-icing, or secondary de-icing. This in itself is not a disaster and weather can happen at any airport and to any airline. The difference is that of course BA with its BoB never actually planned on what they would do for pax that were severely delayed, even if it puts BA in a situation where they are actually breaking regulations. I find it ironic that Sr. Cruz, just days after his asinine comments about "very short haul" flights is now in a position where yesterday's IST pax are possibly STILL in transit to LHR, a dozen hours later, after being delayed, then circling London forever, then landing in Liverpool, and I would hope somehow now in London, yet they probably were not given a cup of water until they deplaned in Liverpool......maybe. There is not even a debate here about drinking the disgusting tank water or not. There simply would not be enough.
You know it is things like dealing with weather and Irrops that is supposed to make people trust airlines like BA. Otherwise they really are Easyjet and Ryanair.