[TesTVWhirl]

You may get a token prerecorded message from some current BBC Three personality if they happened to be filming something recently and could tack something on easily. But yeah I think by the nature of the channel it's very unlikely they'll do much by way of old channel nostalgia. For one thing they have such a narrow target audience of 16-30(ish) that they wouldn't be expecting many people who would actually remember any of the older branding to still be watching now.

There's also BBC Four you can look at as a bit of a similar precedent from recent times. That's a channel much more focused on nostalgia and archive programming, and for their 20th there were a few special continuity announcements recorded but not a lot else.