Not my area usually but big cats in the British countryside are genuinely one of those phenomena that sit right on the edge of what I find credible. There's just too many credible witness reports across decades to dismiss entirely, and Shropshire has come up before in the historical sightings data.
That said I'd want to know more about the conditions. Time of day, distance, whether you had anything to compare the size against. The number of "big cat" sightings that turn out to be large domestic moggies or even foxes at dusk is honestly embarrasing. People are terrible at judging scale in open countryside.
But if you're confident in what you saw, post everything you remember. Even stuff that seems irrelevant. Did it move in a particular way? Big cats have a very distinctive shoulder roll when they walk, completely different to anything domestic. That detail alone would make me take this a lot more seriously.