We are still waiting for IRS guidance regarding this. If the IRS does not use the same means for the stimulus check as for the tax refund, then they will mail the check to the address on the most recently filed tax return they have on record for you.
Once things are finalized we will be able to provide more guidance. You can also stay updated by checking back on the following links.
https://turbotax.intuit.com/coronavirus/
https://www.irs.gov/coronavirus
You will want to update the IRS about any applicable address change you may have had since you filed your most recent tax return. Please refer to Update My Information for more information.