You can add the two trips on one line, however, the maximum deduction for travel benefits you can claim for each eligible trip is the lowest of the following 3 amounts:
- the value of the taxable travel benefit received from your employer
- the actual amount that you spent on your trip
- the lowest return airfare available at the time of the trip between the airport closest to your residence and the nearest designated city to that airport (the nearest designated cities are: Vancouver, BC, Calgary, AB, Edmonton, AB, Saskatoon, SK, Winnipeg, MB, North Bay, ON, Toronto, ON, Ottawa, ON, Montréal, QC, Québec, QC, Moncton, NB, Halifax, NS, St. John's, NL)
I hope this was helpful