The numbers denote the specific variant, like the engine type and max take-off weight. Airbus has the NEO series (new engines) so they add the N. They’re just all model identifiers, like your car may be a GT or XLT or SE.

Thank goodness for the stardate!

Lemminists alone works too

Technically you only need to register in one instance and can interact across lemmy and kbin instances, but you can register the same username in various instances in case of defederation. Lemm.ee federates with all and all instances federate with it for example, beehaw.org doesn’t allow signups and has defederated lemmy.world and sh.itjust.works.