Maybe a stupid question but I just need it clearing up :)

Yes you could, declare him as a horse and jump him in the horse classes - he could
be changed back to a pony for a junior jockey after that season but not within the same season.
 
You'd need to register him as a horse and jump in the horse classes. One thing you'd need to take into consideration is how you pony would cope jumping on a horse's stride, some are fine but others struggle with the distances.
 
yeah he can deffo jump as a horse but not a pony

im gonna jump my 145cm pony as a horse when im out of ponies but im gonna take him on a ticket a few times to see how he copes with striding before i register him :)
 
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