In essence your points are well placed. Menzies future may not be very secure but EI could still operate but just not have base planes or crew. I think the sun routes are indeed probably dead in the water. I would say we mite get a year or so with LHR. LGW depends on who takes up the slots.
I would say though that once the takeover starts moving it will be a very quick process but it's not a takeover as in BMI or BCAL so maybe not all gloom for BHD