Mystery 4x5 film: FP3?

I have a strange compulsion to buy old film...I picked this up for cheap:


"made in England" suggests Ilford (rebranded, of course) or perhaps Kentmere?
2 u-notches, closer together than FP4 (non-plus)?
It is on thick polyester, with a thick, slimy emulsion, suggesting the film is an older formula than the box labeling appears (sans serif type always looks modern...)
I'll post a scan of the initial test shot in a minute--it's on a different computer...

D76 1:1, 10min at 70*

Shot in late afternoon light, red 25 filter. More dramatic contrast than I expected, almost IR-like. (There is direct sun on some of the trees.)
Thick, slimy, easily scratched emulsion. I should drag out some hardening fix.

What do the film code notches look like on the exposed neg?

Axle said:

What do the film code notches look like on the exposed neg?

Click to expand...

Picture of the notches in the first post.
I would say it is old FP3 from the 1960's where they introduced the ASA 125.

Thanks for looking!
I have found pictures showing two notches for "early FP4" but none for FP3. The early FP4 notches look more widely spaced...
I also have some 1950s Kodak (royal, for example) that has a similar thick base, but not the thick slimy emulsion, and none of the Eastern European films do either.