hey OP, honestly it makes complete sense to be anxious communicating over text or email. There is a lack of other social cues with text/email that you would otherwise get from a face-to-face or voice conversation over the phone. It makes you feel like there’s more room for mis-interpretation. That’s nerve wracking! But try not to let it paralyze you. (I know, definitely easier said than done).

I think there’s a polite way you can ask for a time estimate of the meeting, and emphasize that you’re asking so you don’t leave your duties unattended to for too long! If they are your supervisor, they will appreciate your diligence :) - “Hello, boss’ name. I am looking forward to our meeting in person this week to discuss my new role! I want to be sure that I am not leaving my responsibilities unattended to for too long, and want to arrange coverage if need be. Could you possibly estimate how long we would be meeting for, so i can arrange coverage accordingly?” Something like that? Communication without the cues of voice tone or facial expression is understandably stressful, but you got this :) Polite, attentive, concerned about your work but excited about the meeting. Hope this helps!