Our BA flight time (am travelling with my teenage daughter) has already been changed from a 21:40 arrival to a 22:15 arrival (VCE)

Ordinarily, I am not concerned as the plan is to board the Alilaguna B departing at 23:20 or 00:20 which would get us to the Lido S.M.E. stop one hour later.

However…. I’m wondering what the best strategy would be if the flight is further delayed.

I understand one can buy the Alilaguna tickets at the Airport before making the 10-15 minute walk/jog down to the pier where the boat is.
However… what if we cleared customs at, say, 00:05, got the tickets, legged it down to the pier but missed the boat?
Would it be better to not try and buy the tickets at the airport but at the ticket machine at the pier itself (assuming it is there)?

My plan B is to get the airport bus (linea 5) that leaves at 01:10am to Piazzale Roma (or a road taxi there) and the N Vaporetto to Lido that departs at 1:42 (and 2:42?)

It’s the getting into the arrivals hall at midnight scenario that bothers me - the potential of madly dashing to reach a boat and losing €30 if we don’t reach it in time.

We’ll have backpacks with 4 days of clothes and wellies, no wheeled luggage.