My understanding is that this has moved well out of the realms of TUPE and any reemployment of Flybe staff would be entirely optional and without any strings.
As for the ditching liabilities and carrying on, it seems that this is quite common these days and thee are several ways of doing it. According to EY's reports, this had been considered as a sort of pre pack administration scheme early on but was dropped due to CAA and OL / AOC issues. Whatever the intentions of the original consortium, after the Coronavirus downturn hit it and given the perilous state of most airlines it would be difficult to claim that there was some kind of scam going down to avoid liabilities.
It would have been interesting to see how they / the courts would have dealt with the pension scheme though.
As for the 400-500m of creditor claims. This figure does look eyewatering but it is a bit of a distraction in that its is a raw snapshot of what was owed the day the company went bust. Had the company been able to continue then much of that debt would have been less and due spread over many years. The pension contributions for instance were due at about 4-5m per year over about 10 years and yet the failure triggered a huge wind up debt. This would happen to any Airline with a DB scheme. It would be interesting to look at a scenario with several other large airlines if they went bust due to cashflow running out. They would all immediately clock up massive debts and for some in particular, a very large pension wind up debt.
There is a long list of Flybe debts on the EY report. Many would have been to suppliers who would probably have preferred the continuation or rescue of Flybe so that they could keep cashflows and contracts. Many would prefer not to go chasing debt with little chance of reclaiming much if any at all.
It may be that the CAA are concerned that this may be just a slot buying selling exercise with a token airline attached but I would be surprised if this was the case. If there was concern then it would be easy for EY to call the purchases bluff or at least get them to show their true intentions with a no embarrassment (don't take the pi**)clause. Obviously if the purchaser was being honest about their intentions to create jobs, help the economy etc then they would have no problem with such a clause. EY did this for the sale of Stobart back to Stobart Group. Some of the unsecured creditors might take an interest in ensuring there was no pi** taking too.
If there are conditions on retaining slots and licences in the deal between FLybe (EY) and Thyme then I assume that Flybe will fall back into the hands of EY and they will have to start all over again.
The CAA might have had some concerns but reading their letter, it does seem that they are being a bit jobs-worth. Clearly its going to be very complex for EY to put together a package but given the desperate jobs market and economic downturn, they could have perhaps been a bit more helpful. It is almost as though they made up their minds and then got their lawyers to make it all fit the laws. Ironically, they seemed to rely entirely on retained EU law.
It will be interesting to see if Flybe (EY) appeals or comes back with another structure and proposal. They have extended the administration for three years so are clearly minded not to just give up.