Each uttering a forgery carries a 5 year prison sentence max, the Grand Theft 3rd also carries a 5 year prison sentence, max, for a total possible jail time of 20 years. Of course, there's little chance of getting that much time, plus uttering a forgery charges can be difficult to prove, the state must jump thru many hoops to get a conviction on uttering a forgery.
Call a local attorney immediately for a better idea of what will happen in your county.
You are looking at 5 years each. Mr. Guidry is correct in how the proceed in these types of cases. I would also add that since this is the second time for this 2 years probation is unlikely and the State may want to seek jail or prison. I handle cases in Hillsborough county if you wish to give me a call at 813-277-0800.