Congrats nice pics. No matter how well you air top an inflatable, will always deflate itself specially boating on cold days, winter time. What was inflated to, will not remain same during the day, worse during afternoons. Inflatables are prone to air, water heat/cold temp fluctuations.
PC, do you inflate that carrier with a pressure gauge, sight or thumb gauge ? as to check how much PSI Sib loses throughout the day. That large Sib needs to be inflated to 3.0 PSI minimum to have good tube & keel rigidity to work nicely along OB nice fuel consumption.
Happy Boating