Airplay

I tried two sort-of random videos on that site, and it didn’t work for skipping around the timeline. I guess (some of) the videos aren’t optimized for seeking and streaming with regard to going beyond what was buffered. Optimizing for streaming is a way of encoding the video, and as well for the server software, which the archivists may not have applied to all videos.

The “download” video option will store locally, while playing, and in the downloaded part, you should be able to skip around somewhat. Depending on your device connection speed and free storage, you may be able to wait for the whole video to buffer locally.

Not much else you can do about it, except express your experience as feedback for the site staff. Their videos behave differently from commercial streaming services.

(controller bar on Mac; I couldn’t discern the buffer tint change on iPhone.)

You should be able to scrub the timeline on the AirPlay sending device, to the moment where you intended to resume.

What type of content are your trying to stream? Is it a purchase from the iTunes Store, or something else? Some content may not allow for FF or RW, if set by the content provider.