There is no class rule that either allows this or forbids it.

The F16 class rules leaves this open to be regulated by the SI or by vote of the other participants in the fleet.

The F16 class rules often do not rule on HOW an event is organised or structured. That is something for the group of people organising the event to decide.

Of course it is expected that you race/finish the event as you have started it and a mid-event change has thus far only been allowed when it was announced before the closure of the registration and when no objections from the fleet was received. I know of only one exception and that was last years (or 2007) Gulfport A-cat/F16 invitational where the wind were so unstable that several 1-up crews asked mid-event if they could hook up to form 2-up crews. It was decided that the 1-up and 2-up results would be handles seperately meaning that several DNS's were recorded for these crews and thus removing any unfairness towards the crews that remained with their original configuration.

Now I know that for alot of people this situation is hard to understand (not that I understand why that is) but the practically speaking each crew finished the event in the setup they started in and only in a fewe special cases was a change allowed. Often measures were taken to garantee that such a change never disadvantaged any "consistant" crews.

It is foremost a possibility to allow people to participate justifying the expenses made to get to the event, it is not a class policy or even an encouraged principle to change setup mid-event. The only thing that is encouraged is the possibility to sail both setups in general or change setups up to the moment of final registration (Changing setup between seperate events).

Wouter