I think better to use a google sheet. In the google sheet you can add columns for bounty thered links, report submit date, bounty rules. You can check the google sheet and do the bounties very neatly. In this way you can manage even 50,60 bounties.
I use Excel table to work with bounty. The Google table is also very convenient, but as a rule I work at home and I always have access to a Microsoft office. In my table I mark active and finished bounties. At the same time I take part in 8 companies and it takes about 2 hours a day.