AVASPORT acro SIZE

Hi, I would like to ask what size to order. I have around 192cm and 87kg . Currently I have SUP AIR acro 3 L and I think that is small for me - seat board ends approx. 20 cm from my knees. But in turbulent conditions I have bad feeling that I floating in this harness also if all straps are tightened. So I considering if to go to XL or XXL size of AVASPORT harness. I have no chance to try it, thats reason why Iam asking.

Thanks for helpful informations