I called mine in at the beginning of last football season. Got like $250 put in my account and played w/ it all season and turned it into a couple grand so I didn't even have to make a deposit last year, which was nice.
Bet Jam will always be my favorite book.
Betjam is surely a fine book, but a bit over-rated, IMO !
I call them Greek-lite.
Greek has way more options.
Jam has the loyalty thing, which makes them like -109, and -105 on Fridays for a few hours.
Best is to have both, and easy with transfers being free.