[Orry Verducci]

The 'no signal detected' screen is indeed a satellite decoder (probably the venerable Ericsson/MediaKind RX8200). The flashes of green are probably brief bits of it outputting invalid SDI video before it noticed and put out the error message instead.
The SIS 'Meida City' bars are actually generated by an encoder (providing a link from Salford to ITV's contribution network, possibly via BT Tower), and pop up on a loss of input. SIS, now NEP Connect, have a downlink station there.
So I think what happened was:
- RF stage loses signal
- Video decoder loses lock, then holds on to the last frame, then outputs black, then a few seconds of no valid video
- IVNP encoder pops up its bars
- Sat decoder starts outputting valid SDI black, which IVNP encoder starts sending again
- Sat decoder outputs signal loss message
- playout director cuts to the reserve, possibly not noticing that it's also on a glitchy freeze frame
- Playout director reaches for their breakdown slide and standby material.

The Signal Loss screen is indeed from a MediaKind RX8200.

I believe the sequence of events are slightly different to what you describe.

It appears to me that ITV Pres were taking their main path from NEP's downlink facility in MediaCity (they're regularly used by ITV for sat downlinks), with the backup path from another downlink facility. The backup may even be one of Red Bee's on site receivers (they have a few).

What we see is NEP losing the signal and whatever is downstream failing over to bars when the decoder stops outputting valid video. The switch to the RX8200's 'No Signal' message would be Pres manually switching to their guard (the backup path), which is obviously also down. The switch between the message and the glitchy frozen frame is characteristic of a RX8200 receiving corrupted data. I look after a few of them and they all do this in similar situations. At that point Pres clearly admit defeat and switch to the fault slate.

To avoid this situation normally ITV insist on main paths being by fibre, with sat links only being permitted on backup paths. However I vaguely recall that in this situation there was something about the venue that made connectivity difficult, so they had to resort to dual satellite links (two satellites, two downlink facilities). The severe weather unfortunately blocked the uplink from both sat trucks.

For live shows delivered via dual satellite ITV now require a lower bitrate internet stream (e.g. SRT) to be provided in to Red Bee as tertiary to avoid similar situations. BT Tower have the capability now to make SRT streams available on their router, which can  be booked straight in to ITV's contribution network (Meganet).