To add the supplier notes, you should head to the dates and prices tab of the corresponding tour:
Homepage > Tours > DATES & PRICES
And after that, please scroll down until the bottom of the page where you can find the option "Update multiple departure dates at once".
Once you are on this screen, first you need to select the departures where to add the supplier notes.
The departure selection depends on how you have previously created your departures. For instance, if you have different product notes, then you can select the departures based on that characteristic.
Or if you have different departure times, then you can select the affected departures by time.
Or if all your departures have same product notes and the same time, then you can select them by date:
Once you have selected the departures where to add the supplier notes, the next step would be to enter the supplier notes themselves.
If you need to add one supplier note for every departure, then you need to repeat this process for every supplier entry note once.