Currently, the Team Calendars options for "repeat on" are "Same date" and "Same day each month". This "Same day each month" option is limited to ascending positions of the days of the week (First, Second, Third, Fourth) and the option for 'Last' occurrence of that day. 

In certain scenarios, for example when trying to schedule events to repeat on the "last two Saturdays of the month",  the current options may fail the match the exact desired criteria depending on the month (In this example, the two last Sat can be third & fourth or fourth & fifth).

This feature request is asking for the possibility of adding a 'Penultimate' option so more recurring events criteria can be met.