Max continuous
All credit to you for trying to gain experience, and it is experience.
However it cannot count towards any licence quotas. But, if you keep a record of the flights, routes etc, at least you can show on a CV that you have a certain number of hours in commercial operations , abeit as a 'passenger', but it is better than nothing.
Why don't you speak to the operator and ask if you could fly the non commercial legs, or some positioning flights as the pilot?
If you don't ask, you don't get!