At 30' x 50' it's the largest such flag in the world. It's flying along I-71 about a mile south of the I-71/I-75 split. The YT video comments have more info.

The SSPX has a giant complex at Walton, Ky. Was the priest at the scene of the unfurling of this flag SSPX?

There is another group, indult, which might also be sponsoring this event. They are in Park Hills, KY, about 15-20 miles north on I-75/71.

Anyone know whodunnit?

The video notes say it's sponsored by Trad Flags, a small company located nearby that sells porch-size versions of various banners. The YT comment section says the flag's on private property within sight of I-71 between exits 72 and 77.

Over at Google Maps, that's indeed exactly the location of Our Lady of the Assumption Church, SSPX. The video shows a lot of shipping containers or some such in the background, and there are several commercial/industrial businesses right at that same spot.

There's a priest standing on the platform at around 1:55 to 2:05 on the video. That priory has seven priests according to the website. Maybe someone recognizes the priest?

And in the crowd there are four nuns in the center and two more off to the left. And two priests in cassocks.
Women are in skirts and some are wearing veils.
And the construction company truck says St Josephs Company Crane Service.

The video notes say it's sponsored by Trad Flags, a small company located nearby that sells porch-size versions of various banners. The YT comment section says the flag's on private property within sight of I-71 between exits 72 and 77.

Over at Google Maps, that's indeed exactly the location of Our Lady of the Assumption Church, SSPX. The video shows a lot of shipping containers or some such in the background, and there are several commercial/industrial businesses right at that same spot.

There's a priest standing on the platform at around 1:55 to 2:05 on the video. That priory has seven priests according to the website. Maybe someone recognizes the priest?

Pretty sure it is Fr. Stanich

The flag is not at the priory. It is at the business location of a courageous, large Catholic family, which has branches in most of the Cincinnati area trad groups. The SSPX priory would not be in Walton without them. 

https://bavarianwaste.com/catholic-flags/

The SSPX has a giant complex at Walton, Ky. Was the priest at the scene of the unfurling of this flag SSPX?

There is another group, indult, which might also be sponsoring this event. They are in Park Hills, KY, about 15-20 miles north on I-75/71.

Anyone know whodunnit?

I know some others have already mentioned parts of this, but as I understand it (I know one of the families who worked on the project) it was a joint effort. There were SSPX involved, as well as some former parishioners of Our Lady of Lourdes in Covington (the Indult TLM Parish that was shut down by the Bishop after the pastor criticised the Novus Ordo 'Mass').

Bavarian Waste and TradFlags.com are owned by two different families, however both very well deserving of any possible support! I personally know the family who owns TradFlags.com (including the teenagers who design their flags), they are absolutely delightful and their flags are of good quality, so would definitely encourage anyone who has a flag pole to buy a flag from them! 

I know some others have already mentioned parts of this, but as I understand it (I know one of the families who worked on the project) it was a joint effort. There were SSPX involved, as well as some former parishioners of Our Lady of Lourdes in Covington (the Indult TLM Parish that was shut down by the Bishop after the pastor criticised the Novus Ordo 'Mass').

Bavarian Waste and TradFlags.com are owned by two different families, however both very well deserving of any possible support! I personally know the family who owns TradFlags.com (including the teenagers who design their flags), they are absolutely delightful and their flags are of good quality, so would definitely encourage anyone who has a flag pole to buy a flag from them!

Ah ha, WFTD! Then I  was correct on both counts. The large family spoken of has components in both Park Hills (OLLourdes) and the SSPX. 

Can you tell me the current status of Frs. Shannon and Sean? It seems there's a diocesan priest now acting as chaplain for their once congregation. I know that Regina Prophetarum is still shut down. Are Shannon and Sean still under interdict?

Thank you!