Searched the group posts, group files, and googled for a new TM7 without the "Arrived by (mode of transportation)" section since there is no need for a TM6 now. I assume this is still a temporary thing hence no updated TM7 form.
I actually left the country this year so the TM6 info I've included for many years is no longer valid.
Should I just put the info I have which is flight number, arriving from info, date, and the airline, or should I leave it all blank?
TLDR : Answer Summary
The TM6 form (arrival/departure card) requirement has been suspended for arrivals by air, so you should leave that field blank on the TM7 application. Including your latest flight details, such as flight number, arrival date, and airline information, is sufficient.