Ive never had a problem walking in with my brood.
It is pretty safe to walk in at anytime Monday-Friday. Saturday & Sunday and Holiday's usually sell out and it would be wise to book your ticket ahead of time online. www.defy.com/silverdale
I usually go Fridays during Kid Jump and I've never had a problem. It can be busy, but my daughter always likes it and she's 4 as well.
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