Show Instrument names only in 1st flow

I have a score with various movements for two pianos and I only want to show “Piano 1/Piano 2” in the first flow, but not in the following flows. How can I achieve this?

Choose “None” for staff labels in the Staves and Systems section of Layout Options. Then, select the first item at the beginning of the first flow in Engrave mode and create a system break. Select the system break’s signpost and choose “Full” in the Staff Label section of the Properties Panel

… I initially wrote “none” in the last sentence of my post. I corrected it, but just in case it was read before my correction, I of course meant “Full”

Thx Claude, that you know this workaround!
I hope that Dorico offers an easier way to do this in future. Such workarounds are not really intuitive. To skip staff labels in flows should be done easier.

Perfect, that did the trick! Thank you, Claude.

I have to disagree with the designation “workaround”. The custom labelling of system breaks is actually a feature. It can be used on any system or frame break. In a lot of octavo choir publications, a new subsection of a piece may had a different grouping of voices. The publisher can then start the piece with all labels showing on the first system, then nothing for three systems in order to save space, then show a subsection where only alto and bass sing for 5 system, in which case those will need one system to display labels, and on-and-on until the end. What the OP asked for is in no way different: he just wanted it to apply to flows. Having said that, having a flow labelling options in layout options might be a nice idea, but is not technically different to what is available now.