The USASF issued a rules clarification. The following skill restrictions apply for Senior Open Level 5:
In tumbling, only single twisting skills are allowed. During a full-twisting tumbling skill, no trick other than the twist is allowed (i.e. including but not limited to: split fulls, hitch kick fulls, X-Fulls, Full-Xouts, etc) and both feet must land and finish on the performing surface. (i.e. no full twisting tumbling to seat, prone body landings or similar).
Clarification: All skills up to a full twist are also allowed. i.e. half twists and arabians.