A riding-school system could connect a lesson booking to an approved horse allocation. A free place in a class does not automatically mean a suitable horse is available for every rider.
Instructors need control over suitability, workload limits and changes. Rider information should be restricted to staff who need it. The booking process may require review before confirmation, particularly for new riders or specialist sessions.
Start with the school's actual allocation rules and test a horse unavailable at short notice, a cover instructor and a rider moving classes. Keep software recommendations separate from final professional judgement. A useful system reveals conflicts and outstanding decisions while leaving riding suitability and welfare decisions with the responsible staff.
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