Looks like he has set up several dates on the dating site and he cannot make up his mind yet. Maybe he has a pattern - goes out with 10 different ladies, narrows it down to five, and goes from there. You are probably in his closer circle, but he is still playing the field, thus keeping in contact with you.
If I were you, I'd text him that you had a great time on the initial date, however, since he hasn't made other arrangements for a second date, you will proceed with other dates you had declined previously. Wish him good luck with his endeavors and let him off the leash. He's a dog!!