I'm sure that they will do no harm but you'll still be under the usual clear in. You should still list it as your first preference just in case the demand is lower this year. In my opinion, transferring into Law is usually an easier process than entering with the 98 ATAR. Next year try and aim for like a 78+ average and you will be in with a very competitive chance of making it into Law!!
Good luck with your application!! Hopefully you'll get straight in! 
I went to a law morning tea like yesterday and I can say the demand is potentially really high this year. The presenter said she hadn't seen so many people before.
I think transferring won't do you any harm, if it happens you don't get in. The way the Arts/Law sequences work is that you don't lose any time or credit for your Arts course \ and will graduate in 5 years like everyone else if you do transfer. It means that instead of half Arts half Law in the first year, you'll be doing all Arts. And in Year 2, you'll be doing all Law (as opposed to half Arts, half Law). Someone double confirm please, just in case I misinterpreted the response.
Good luck, see you around