You need to correct your words. Two. "Dead Head" are miles you are not carrying or seeking a ride. Aviation and public transit uses this for being out of service. You tell any tax person about "Dead Head" and they will be discarded. The operative word is "Cruising". You are available for your next ride, you are in service, you are working.
I have been in audits with clients, I was trained about audits by the IRS and employees of same, and I was audited before my job because IRS new hires have mandatory three year audits of all items. My understanding is that rideshare is beleagured by a widespread ignorance about how it should be characterized. People who have rights to win audits are losing them to the misunderstandings. Speak clearly to your tax professional about what you do between rides. Never call a time you are available "Dead Head".
Call it "Cruising". The misunderstanding will clear up.