Manchester to Orlando - advice travelling with 4yo with additional needs

[NavyKitchen]

Travelling to Orlando in August with my sister and our families. DN (will be almost 4) has limited verbal communication, is under investigation for possible ASD.
Any hints and tips for the airports and flights (Virgin) for assistance we can request for things like queues, which he will struggle with.
We know we get DAS at Disney and the Universal equivalent but looking for experience from people who have done this particular flight (especially from Manchester with Virgin)

Do request special assistance, think about things like will it help if DS boards first or last and disembarks first or last. With a sunflower lanyard you can use the priority lane at security but it can still be busy. If you are travelling from terminal 1 there is a quieter room.

Thanks. I saw that about Terminal 1, unfortunately we're Terminal 2.

Anyone else?